Records |
Author |
Dixit, H.; Tandon, N.; Cottenier, S.; Saniz, R.; Lamoen, D.; Partoens, B.; van Speybroeck, V.; Waroquier, M. |
Title |
Electronic structure and band gap of zinc spinel oxides beyond LDA : ZnAl2O4, ZnGa2O4 and ZnIn2O4 |
Type |
A1 Journal article |
Year |
2011 |
Publication |
New journal of physics |
Abbreviated Journal |
New J Phys |
Volume |
13 |
Issue |
6 |
Pages |
063002-063002,11 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
Abstract |
We examine the electronic structure of the family of ternary zinc spinel oxides ZnX2O4 (X=Al, Ga and In). The band gap of ZnAl2O4 calculated using density functional theory (DFT) is 4.25 eV and is overestimated compared with the experimental value of 3.83.9 eV. The DFT band gap of ZnGa2O4 is 2.82 eV and is underestimated compared with the experimental value of 4.45.0 eV. Since DFT typically underestimates the band gap in the oxide system, the experimental measurements for ZnAl2O4 probably require a correction. We use two first-principles techniques capable of describing accurately the excited states of semiconductors, namely the GW approximation and the modified BeckeJohnson (MBJ) potential approximation, to calculate the band gap of ZnX2O4. The GW and MBJ band gaps are in good agreement with each other. In the case of ZnAl2O4, the predicted band gap values are >6 eV, i.e. ~2 eV larger than the only reported experimental value. We expect future experimental work to confirm our results. Our calculations of the electron effective masses and the second band gap indicate that these compounds are very good candidates to act as transparent conducting host materials. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000292137500002 |
Publication Date |
2011-06-03 |
Series Editor |
|
Series Title |
|
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 |
3.786 |
Times cited |
98 |
Open Access |
|
Notes |
Iwt; Fwo; Bof-Noi |
Approved |
Most recent IF: 3.786; 2011 IF: 4.177 |
Call Number |
UA @ lucian @ c:irua:89555 |
Serial |
1008 |
Permanent link to this record |
|
|
|
Author |
Silhanek, A.V.; Leo, A.; Grimaldi, G.; Berdiyorov, G.R.; Milošević, M.V.; Nigro, A.; Pace, S.; Verellen, N.; Gillijns, W.; Metlushko, V.; Ilić, B.; Zhu, X.; Moshchalkov, V.V.; |
Title |
Influence of artificial pinning on vortex lattice instability in superconducting films |
Type |
A1 Journal article |
Year |
2012 |
Publication |
New journal of physics |
Abbreviated Journal |
New J Phys |
Volume |
14 |
Issue |
|
Pages |
053006-053006,11 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
In superconducting films under an applied dc current, we analyze experimentally and theoretically the influence of engineered pinning on the vortex velocity at which the flux-flow dissipation undergoes an abrupt transition from low to high resistance. We argue, based on a nonuniform distribution of vortex velocity in the sample, that in strongly disordered systems the mean critical vortex velocity for flux-flow instability (i) has a nonmonotonic dependence on magnetic field and (ii) decreases as the pinning strength is increased. These findings challenge the generally accepted microscopic model of Larkin and Ovchinnikov (1979 J. Low. Temp. Phys. 34 409) and all subsequent refinements of this model which ignore the presence of pinning centers. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000304871700003 |
Publication Date |
2012-05-04 |
Series Editor |
|
Series Title |
|
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 |
3.786 |
Times cited |
40 |
Open Access |
|
Notes |
; This work was supported by the Methusalem Funding of the Flemish Government, the ESF-NES program, the Belgian Science Policy (IAP) and the Fund for Scientific Research-Flanders (FWO-Vlaanderen). AVS, GRB and WG received individual support from FWO-Vlaanderen. GG acknowledges support from the research project L.R. N5 of Regione Campania. VM acknowledges financial support from the US NSF, grant no. ECCS-0823813. We acknowledge J Van de Vondel for a critical reading of the manuscript. ; |
Approved |
Most recent IF: 3.786; 2012 IF: 4.063 |
Call Number |
UA @ lucian @ c:irua:98949 |
Serial |
1616 |
Permanent link to this record |
|
|
|
Author |
Masir, M.R.; Vasilopoulos, P.; Peeters, F.M. |
Title |
Magnetic Kronig-Penney model for Dirac electrons in single-layer graphene |
Type |
A1 Journal article |
Year |
2009 |
Publication |
New journal of physics |
Abbreviated Journal |
New J Phys |
Volume |
11 |
Issue |
|
Pages |
095009,1-095009,21 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
he properties of Dirac electrons in a magnetic superlattice (SL) on graphene consisting of very high and thin (δ-function) barriers are investigated. We obtain the energy spectrum analytically and study the transmission through a finite number of barriers. The results are contrasted with those for electrons described by the Schrödinger equation. In addition, a collimation of an incident beam of electrons is obtained along the direction perpendicular to that of the SL. We also highlight an analogy with optical media in which the refractive index varies in space. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000270513500008 |
Publication Date |
2009-10-01 |
Series Editor |
|
Series Title |
|
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 |
3.786 |
Times cited |
89 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.786; 2009 IF: 3.312 |
Call Number |
UA @ lucian @ c:irua:79241 |
Serial |
1884 |
Permanent link to this record |
|
|
|
Author |
Alexandrov, A.L.; Schweigert, I.V.; Peeters, F.M. |
Title |
A non-Maxwellian kinetic approach for charging of dust particles in discharge plasmas |
Type |
A1 Journal article |
Year |
2008 |
Publication |
New journal of physics |
Abbreviated Journal |
New J Phys |
Volume |
10 |
Issue |
|
Pages |
093025,1-093025,12 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Nanoparticle charging in a capacitively coupled radio frequency discharge in argon is studied using a particle in cell Monte Carlo collisions method. The plasma parameters and dust potential were calculated self-consistently for different unmovable dust profiles. A new method for definition of the dust floating potential is proposed, based on the information about electron and ion energy distribution functions, obtained during the kinetic simulations. This approach provides an accurate balance of the electron and ion currents on the dust particle surface and allows us to precisely calculate the dust floating potential. A comparison of the obtained floating potentials with the results of the traditional orbital motion limit (OML) theory shows that in the presence of the ion resonant charge exchange collisions, even when the OML approximation is valid, its results are correct only in the region of a weak electric field, where the ion drift velocity is much smaller than the thermal one. With increasing ion drift velocity, the absolute value of the calculated dust potential becomes significantly smaller than the theory predicts. This is explained by a non-Maxwellian shape of the ion energy distribution function for the case of fast ion drift. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000259615700004 |
Publication Date |
2008-09-24 |
Series Editor |
|
Series Title |
|
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 |
3.786 |
Times cited |
19 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.786; 2008 IF: 3.440 |
Call Number |
UA @ lucian @ c:irua:76519 |
Serial |
2348 |
Permanent link to this record |
|
|
|
Author |
Villegas, C.E.P.; Tavares, M.R.S.; Hai, G.-Q.; Peeters, F.M. |
Title |
Sorting the modes contributing to guidance in strain-induced graphene waveguides |
Type |
A1 Journal article |
Year |
2013 |
Publication |
New journal of physics |
Abbreviated Journal |
New J Phys |
Volume |
15 |
Issue |
|
Pages |
023015-11 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We propose a simple way of probing the number of modes contributing to the channeling in graphene waveguides which are formed by a gauge potential produced by mechanical strain. The energy mode structure for both homogeneous and non-homogeneous strain regimes is carefully studied using the continuum description of the Dirac equation. We found that high strain values privilege negative (instead of positive) group velocities throughout the guidance, sorting the types of modes flowing through it. We also show how the effect of a substrate-induced gap competes against the strain. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000314868000002 |
Publication Date |
2013-02-08 |
Series Editor |
|
Series Title |
|
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 |
3.786 |
Times cited |
7 |
Open Access |
|
Notes |
; This work was supported by FAPESP, CNPq and the Flemish Science Foundation (FWO-VI). ; |
Approved |
Most recent IF: 3.786; 2013 IF: 3.671 |
Call Number |
UA @ lucian @ c:irua:107667 |
Serial |
3056 |
Permanent link to this record |
|
|
|
Author |
Verlackt, C.C.W.; Neyts, E.C.; Jacob, T.; Fantauzzi, D.; Golkaram, M.; Shin, Y.-K.; van Duin, A.C.T.; Bogaerts, A. |
Title |
Atomic-scale insight into the interactions between hydroxyl radicals and DNA in solution using the ReaxFF reactive force field |
Type |
A1 Journal article |
Year |
2015 |
Publication |
New journal of physics |
Abbreviated Journal |
New J Phys |
Volume |
17 |
Issue |
17 |
Pages |
103005 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
Cold atmospheric pressure plasmas have proven to provide an alternative treatment of cancer by targeting tumorous cells while leaving their healthy counterparts unharmed. However, the underlying mechanisms of the plasma–cell interactions are not yet fully understood. Reactive oxygen species, and in particular hydroxyl radicals (OH), are known to play a crucial role in plasma driven apoptosis of
malignant cells. In this paper we investigate the interaction of OH radicals, as well as H2O2 molecules and HO2 radicals, with DNA by means of reactive molecular dynamics simulations using the ReaxFF force field. Our results provide atomic-scale insight into the dynamics of oxidative stress on DNA caused by the OH radicals, while H2O2 molecules appear not reactive within the considered timescale. Among the observed processes are the formation of 8-OH-adduct radicals, forming the first stages towards the formation of 8-oxoGua and 8-oxoAde, H-abstraction reactions of the amines, and the partial opening of loose DNA ends in aqueous solution. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000367328100001 |
Publication Date |
2015-10-02 |
Series Editor |
|
Series Title |
|
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 |
3.786 |
Times cited |
18 |
Open Access |
|
Notes |
CCWV,ECN and AB acknowledge the contribution of J Van Beeck who is investigating the interaction between H2O2 andDNAusingrMDsimulations. Furthermore, they acknowledge financial support from the Fund for Scientific Research—Flanders (project number G012413N). The calculations were performed using the Turing HPCinfrastructure at the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the Universiteit Antwerpen. TJ and DF gratefully acknowledge support from the European Research Council through the ERC-Starting GrantTHEOFUN(Grant Agreement No. 259608). |
Approved |
Most recent IF: 3.786; 2015 IF: 3.558 |
Call Number |
c:irua:129178 |
Serial |
3955 |
Permanent link to this record |
|
|
|
Author |
Yusupov, M.; Saraiva, M.; Depla, D.; Bogaerts, A. |
Title |
Sputter deposition of MgxAlyOz thin films in a dual-magnetron device : a multi-species Monte Carlo model |
Type |
A1 Journal article |
Year |
2012 |
Publication |
New journal of physics |
Abbreviated Journal |
New J Phys |
Volume |
14 |
Issue |
7 |
Pages |
073043 |
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
Abstract |
A multi-species Monte Carlo (MC) model, combined with an analytical surface model, has been developed in order to investigate the general plasma processes occurring during the sputter deposition of complex oxide films in a dual-magnetron sputter deposition system. The important plasma species, such as electrons, Ar+ ions, fast Ar atoms and sputtered metal atoms (i.e. Mg and Al atoms) are described with the so-called multi-species MC model, whereas the deposition of MgxAlyOz films is treated by an analytical surface model. Targetsubstrate distances for both magnetrons in the dual-magnetron setup are varied for the purpose of growing stoichiometric complex oxide thin films. The metal atoms are sputtered from pure metallic targets, whereas the oxygen flux is only directed toward the substrate and is high enough to obtain fully oxidized thin films but low enough to avoid target poisoning. The calculations correspond to typical experimental conditions applied to grow these complex oxide films. In this paper, some calculation results are shown, such as the densities of various plasma species, their fluxes toward the targets and substrate, the deposition rates, as well as the film stoichiometry. Moreover, some results of the combined model are compared with experimental observations. Note that this is the first complete model, which can be applied for large and complicated magnetron reactor geometries, such as dual-magnetron configurations. With this model, we are able to describe all important plasma species as well as the deposition process. It can also be used to predict film stoichiometries of complex oxide films on the substrate. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000307072500003 |
Publication Date |
2012-07-21 |
Series Editor |
|
Series Title |
|
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 |
3.786 |
Times cited |
2 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.786; 2012 IF: 4.063 |
Call Number |
UA @ lucian @ c:irua:100100 |
Serial |
3111 |
Permanent link to this record |
|
|
|
Author |
Apolinario, S.W.S.; Partoens, B.; Peeters, F.M. |
Title |
Structural and dynamical aspects of small three-dimensional spherical Coulomb clusters |
Type |
A1 Journal article |
Year |
2007 |
Publication |
New journal of physics |
Abbreviated Journal |
New J Phys |
Volume |
9 |
Issue |
|
Pages |
283,1-29 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000249112500001 |
Publication Date |
2007-08-25 |
Series Editor |
|
Series Title |
|
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 |
3.786 |
Times cited |
44 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.786; 2007 IF: 3.264 |
Call Number |
UA @ lucian @ c:irua:66120 |
Serial |
3193 |
Permanent link to this record |
|
|
|
Author |
Kong, M.; Partoens, B.; Peeters, F.M. |
Title |
Structural, dynamical and melting properties of two-dimensional clusters of complex plasmas |
Type |
A1 Journal article |
Year |
2003 |
Publication |
New journal of physics |
Abbreviated Journal |
New J Phys |
Volume |
5 |
Issue |
|
Pages |
23,1-17 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000181548000008 |
Publication Date |
2003-03-15 |
Series Editor |
|
Series Title |
|
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 |
3.786 |
Times cited |
67 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.786; 2003 IF: 2.480 |
Call Number |
UA @ lucian @ c:irua:62452 |
Serial |
3232 |
Permanent link to this record |
|
|
|
Author |
Xu, B.; Milošević, M.V.; Peeters, F.M. |
Title |
Vortex matter in oblate mesoscopic superconductors with a hole: broken symmetry vortex states and multi-vortex entry |
Type |
A1 Journal article |
Year |
2009 |
Publication |
New journal of physics |
Abbreviated Journal |
New J Phys |
Volume |
11 |
Issue |
|
Pages |
013020,1-013020,21 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Using three-dimensional (3D) numerical discretization of the GinzburgLandau (GL) equations, we investigate the superconducting state of a sphere with a piercing hole in the presence of a magnetic field. In the case of samples with central perforation, in axially applied homogeneous magnetic field, we realized unconventional vortex states of broken symmetry due to complex, 3D competing interactions, which depend on the GL parameter ê. For certain sizes of the sample, non-hysteretic multi-vortex entry and exit is predicted with the non-existence of some vorticities as stable states. In a tilted magnetic field, we studied the gradual transformation of 3D flux patterns into 1D vortex chains, where vortices align along the perforation, and the evolvement of the multi-vortex entry as well. We analyze the flux-guiding ability of the hole in a tilted field, which leads to fractional flux response in magnetization M(H) curves. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000262932500003 |
Publication Date |
2009-01-17 |
Series Editor |
|
Series Title |
|
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 |
3.786 |
Times cited |
8 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.786; 2009 IF: 3.312 |
Call Number |
UA @ lucian @ c:irua:75986 |
Serial |
3873 |
Permanent link to this record |
|
|
|
Author |
Klimin, S.N.; Tempere, J.; Milošević, M.V. |
Title |
Diversified vortex phase diagram for a rotating trapped two-band Fermi gas in the BCS-BEC crossover |
Type |
A1 Journal article |
Year |
2018 |
Publication |
New journal of physics |
Abbreviated Journal |
New J Phys |
Volume |
20 |
Issue |
20 |
Pages |
025010 |
Keywords |
A1 Journal article; Theory of quantum systems and complex systems; Condensed Matter Theory (CMT) |
Abstract |
We report the equilibrium vortex phase diagram of a rotating two-band Fermi gas confined to a cylindrically symmetric parabolic trapping potential, using the recently developed finite-temperature effective field theory (Klimin et al 2016 Phys. Rev. A 94 023620). A non-monotonic resonant dependence of the free energy as a function of the temperature and the rotation frequency is revealed for a two-band superfluid. We particularly focus on novel features that appear as a result of interband interactions and can be experimentally resolved. The resonant dependence of the free energy is directly manifested in vortex phase diagrams, where areas of stability for both integer and fractional vortex states are found. The study embraces the BCS-BEC crossover regime and the entire temperature range below the critical temperature T-c. Significantly different behavior of vortex matter as a function of the interband coupling is revealed in the BCS and BEC regimes. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
Language |
|
Wos |
000426002900001 |
Publication Date |
2018-02-05 |
Series Editor |
|
Series Title |
|
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 |
3.786 |
Times cited |
6 |
Open Access |
|
Notes |
; We thank C A R Sa de Melo and N Verhelst for valuable discussions. This work has been supported by the Research Foundation-Flanders (FWO-Vl), project nrs. G.0115.12N, G.0119.12N, G.0122.12N, G.0429.15N, G.0666.16N, by the Scientific Research Network of the Flemish Research Foundation, WO.033.09N, and by the Research Fund of the University of Antwerp. ; |
Approved |
Most recent IF: 3.786 |
Call Number |
UA @ lucian @ c:irua:149909UA @ admin @ c:irua:149909 |
Serial |
4930 |
Permanent link to this record |
|
|
|
Author |
Xue, C.; He, A.; Milošević, M.V.; Silhanek, A., V; Zhou, Y.-H. |
Title |
Open circuit voltage generated by dragging superconducting vortices with a dynamic pinning potential |
Type |
A1 Journal article |
Year |
2019 |
Publication |
New journal of physics |
Abbreviated Journal |
New J Phys |
Volume |
21 |
Issue |
11 |
Pages |
113044 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
We theoretically investigate, through Ginzburg?Landau simulations, the possibility to induce an open circuit voltage in absence of applied current, by dragging superconducting vortices with a dynamic pinning array as for instance that created by a nearby sliding vortex lattice or moving laser spots. Different dynamic regimes, such as synchronous vortex motion or dynamic vortex chains consisting of laggard vortices, can be observed by varying the velocity of the sliding pinning potential and the applied magnetic field. Additionally, due to the edge barrier, significantly different induced voltage is found depending on whether the vortices are dragged along the superconducting strip or perpendicular to the lateral edges. The output voltage in the proposed mesoscopic superconducting dynamo can be tuned by varying size, density and directions of the sliding pinning potential. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000498853700001 |
Publication Date |
2019-11-05 |
Series Editor |
|
Series Title |
|
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 |
3.786 |
Times cited |
6 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 3.786 |
Call Number |
UA @ admin @ c:irua:165158 |
Serial |
6317 |
Permanent link to this record |
|
|
|
Author |
Sabzalipour, A.; Mir, M.; Zarenia, M.; Partoens, B. |
Title |
Two distinctive regimes in the charge transport of a magnetic topological ultra thin film |
Type |
A1 Journal article |
Year |
2020 |
Publication |
New Journal Of Physics |
Abbreviated Journal |
New J Phys |
Volume |
22 |
Issue |
12 |
Pages |
123004 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
The effect of the magnetic impurities on the charge transport in a magnetic topological ultra-thin film (MTF) is analytically investigated by applying the semi-classical Boltzmann framework through a modified relaxation-time approximation. Our results for the relaxation time of electrons as well as the charge conductivity of the system exhibit two distinct regimes of transport. We show that the generated charge current in a MTF is always dissipative and anisotropic when both conduction bands are involved in the charge transport. The magnetic impurities induce a chirality selection rule for the transitions of electrons which can be altered by changing the orientation of the magnetic impurities. On the other hand, when a single conduction band participates in the charge transport, the resistivity is isotropic and can be entirely suppressed due to the corresponding chirality selection rule. Our findings propose a method to determine an onset thickness at which a crossover from a three-dimensional magnetic topological insulator to a (two-dimensional) MTF occurs. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000596436300001 |
Publication Date |
2020-11-11 |
Series Editor |
|
Series Title |
|
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 |
2 |
Open Access |
|
Notes |
; MZ acknowledges support from the U.S. Department of Energy (Office of Science) under Grant No. DE-FG02- 05ER46203. ; |
Approved |
Most recent IF: 3.3; 2020 IF: 3.786 |
Call Number |
UA @ admin @ c:irua:174387 |
Serial |
6701 |
Permanent link to this record |
|
|
|
Author |
Chen, X.; Li, L.; Peeters, F.M.; Sanyal, B. |
Title |
Two-dimensional oxygen functionalized honeycomb and zigzag dumbbell silicene with robust Dirac cones |
Type |
A1 Journal article |
Year |
2021 |
Publication |
New Journal Of Physics |
Abbreviated Journal |
New J Phys |
Volume |
23 |
Issue |
2 |
Pages |
023007 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Dumbbell-like structures are recently found to be energetically favored in group IV two-dimensional (2D) materials, exhibiting rich physics and many interesting properties. In this paper, using first-principles calculations, we have investigated the oxidized form of the hexagonal honeycomb (ODB-h) and zigzag dumbbell silicene (ODB-z). We confirm that both oxidization processes are energetically favorable, and their phonon spectra further demonstrate the dynamic stability. Contrary to the pristine dumbbell silicene structures (PDB-h and PDB-z silicene), these oxidized products ODB-h and ODB-z silicene are both semimetals with Dirac cones at the Fermi level. The Dirac cones of ODB-h and ODB-z silicene are at the K point and between Y and Gamma points respectively, possessing high Fermi velocities of 3.1 x 10(5) m s(-1) (ODB-h) and 2.9-3.4 x 10(5) m s(-1) (ODB-z). The origin of the Dirac cones is further explained by tight-binding models. The semimetallic properties of ODB-h and ODB-z are sensitive to compression due to the self-absorption effect, but quite robust against the tensile strain. These outstanding properties make oxidized dumbbell silicene a promising material for quantum computing and high-speed electronic devices. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000616114900001 |
Publication Date |
2021-01-14 |
Series Editor |
|
Series Title |
|
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 |
3.786 |
Times cited |
2 |
Open Access |
OpenAccess |
Notes |
|
Approved |
Most recent IF: 3.786 |
Call Number |
UA @ admin @ c:irua:176575 |
Serial |
6741 |
Permanent link to this record |
|
|
|
Author |
Chen, Q.; Guo, A.-M.; Liu, J.; Peeters, F.M.; Sun, Q.-F. |
Title |
Topological phase transitions and Majorana zero modes in DNA double helix coupled to s-wave superconductors |
Type |
A1 Journal article |
Year |
2021 |
Publication |
New Journal Of Physics |
Abbreviated Journal |
New J Phys |
Volume |
23 |
Issue |
9 |
Pages |
093047 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Topological properties of a double-stranded DNA (dsDNA) proximity-coupled by an s-wave superconductor are investigated, in which the energy spectra and the differential conductance are calculated within the framework of tight-binding approximation. Our results indicate that this dsDNA-superconductor system hosts Majorana zero modes (MZMs) when the Zeeman field is perpendicular to the helix axis, whereas no MZM could be observed when the Zeeman field is parallel to the helix axis, in sharp contrast to previous studies on nanowires including single-stranded DNA. In particular, two topological phase transitions could take place in the dsDNA-superconductor system by changing the Zeeman field, one from a topological trivial phase to a topological nontrivial phase with one pair of MZMs in small Zeeman field regime, and the other from a phase with one pair of MZMs to a phase with two pairs of MZMs by further increasing the Zeeman field. In the presence of a gate field normal to the helix axis, the topological nontrivial phase with two pairs of MZMs can transform into the phase with one pair of MZMs. The topological phase with one pair of MZMs is more stable and robust against Anderson disorder. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000702122000001 |
Publication Date |
2021-09-15 |
Series Editor |
|
Series Title |
|
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 |
3.786 |
Times cited |
7 |
Open Access |
OpenAccess |
Notes |
|
Approved |
Most recent IF: 3.786 |
Call Number |
UA @ admin @ c:irua:182597 |
Serial |
7033 |
Permanent link to this record |
|
|
|
Author |
Kosov, A.D.; Dubrinina, T.V.; Borisova, N.E.; Ivanov, A.V.; Drozdov, K.A.; Trashin, S.A.; De Wael, K.; Kotova, M.S.; Tomilova, L.G. |
Title |
Novel phenyl-substituted pyrazinoporphyrazine complexes of rare-earth elements : optimized synthetic protocols and physicochemical properties |
Type |
A1 Journal article |
Year |
2019 |
Publication |
New journal of chemistry |
Abbreviated Journal |
New J Chem |
Volume |
43 |
Issue |
7 |
Pages |
3153-3161 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Novel synthetic protocols based on both template and multi-step methods were developed for phenyl-substituted pyrazinoporphyrazine complexes of rare-earth elements (Y, Eu, Gd, Dy, Er and Lu). p-Hydroquinone was employed as a reaction medium and as a reducing agent in the process of porphyrazine macrocycle formation. Both thermal and microwave irradiation techniques were successfully applied for activation of the template macrocyclization process. An alternative multi-step approach involving the initial stage of free-base ligand formation was realized for the lutetium compound. The target complexes were identified by high-resolution mass spectrometry, infrared spectroscopy and nuclear magnetic resonance (NMR) spectroscopy. Electrochemical behavior in solution and UV-vis absorbance in solutions and films were studied as well. Shifts in the position of the Q band and oxidationreduction potentials in comparison with corresponding phthalocyanine analogues were noticed. Using the IR absorption spectra recorded in the temperature range of 170300 K, the position of the Fermi level of −4.7 ± 0.1 eV and a characteristic energy diagram were obtained for the erbium complex. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000459944500035 |
Publication Date |
2019-01-23 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1144-0546 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.269 |
Times cited |
1 |
Open Access |
|
Notes |
; We are grateful for main financial support from the Russian Foundation for Basic Research (Grant No. 16-33-60005 and 18-33-00519). Investigation of optical properties was supported by the Russian Science Foundation (Grant 17-13-01197). Electrochemical investigations were supported by ERA.Net RUS Plus Plasmon Electrolight and FWO funding (RFBR No. 18-53-76006 ERA). We also thank the Council under the President of the Russian Federation for State Support of Young Scientists and Leading Scientific Schools (Grants MK-3115.2018.3) and partial support from the framework of the State Assignment of 2019 (Theme 45.5 Creation of compounds with given physicochemical properties). Investigation of electrophysical properties was supported by the RFBR (Grant 16-07-00961). K. A. Drozdov and M. S. Kotova thank Prof. L. I. Ryabova for productive discussion of the electrophysical data. ; |
Approved |
Most recent IF: 3.269 |
Call Number |
UA @ admin @ c:irua:156555 |
Serial |
5750 |
Permanent link to this record |
|
|
|
Author |
Bafekry, A.; Nguyen, C.; Obeid, M.M.; Ghergherehchi, M. |
Title |
Modulating the electro-optical properties of doped C₃N monolayers and graphene bilayersviamechanical strain and pressure |
Type |
A1 Journal article |
Year |
2020 |
Publication |
New Journal Of Chemistry |
Abbreviated Journal |
New J Chem |
Volume |
44 |
Issue |
36 |
Pages |
15785-15792 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
In this work, we investigated systematically the electronic and optical properties of B doped C3N monolayers as well as B and N doped graphene bilayers (BN-Gr@2L). We found that the doping of B atoms leads to an enlarged band gap of the C3N monolayer and when the dopant concentration reaches 12.5%, an indirect-to-direct band gap switching occurs. In addition, with co-doping of B and N atoms on the graphene monolayer in the hexagonal configuration, an electronic transition from semi-metal to semiconductor occurs. Our optical results for B-C3N show a broad absorption spectrum in a wide visible range starting from 400 nm to 1000 nm with strong absorption intensity, making it a suitable candidate for nanoelectronic and optoelectronic applications. Interestingly, a transition from semi-metal to semiconductor emerges in the graphene monolayer with doping of B and N atoms. Furthermore, our results demonstrate that the in-plane strain and out-of-plane strain (pressure) can modulate the band gap of the BN-Gr@2L. The controllable electronic properties and optical features of the doped graphene bilayer by strain engineering may facilitate their practical performance for various applications in future. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000571972400054 |
Publication Date |
2020-08-18 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1144-0546 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.3 |
Times cited |
7 |
Open Access |
|
Notes |
; This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korean government (MSIT) (NRF-2017R1A2B2011989). ; |
Approved |
Most recent IF: 3.3; 2020 IF: 3.269 |
Call Number |
UA @ admin @ c:irua:171936 |
Serial |
6561 |
Permanent link to this record |
|
|
|
Author |
Bafekry, A.; Faraji, M.; Ziabari, A.A.; Fadlallah, M.M.; Nguyen, C., V; Ghergherehchi, M.; Feghhi, S.A.H. |
Title |
A van der Waals heterostructure of MoS₂/MoSi₂N₄ : a first-principles study |
Type |
A1 Journal article |
Year |
2021 |
Publication |
New Journal Of Chemistry |
Abbreviated Journal |
New J Chem |
Volume |
45 |
Issue |
18 |
Pages |
8291-8296 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Motivated by the successful preparation of MoSi2N4 monolayers in the last year [Y.-L. Hong et al., Science, 2020, 369, 670-674], we investigate the structural, electronic and optical properties of the MoS2/MoSi2N4 heterostructure (HTS). The phonon dispersion and the binding energy calculations refer to the stability of the HTS. The heterostructure has an indirect bandgap of 1.26 (1.84) eV using PBE (HSE06) which is smaller than the corresponding value of MoSi2N4 and MoS2 monolayers. We find that the work function of the MoS2/MoSi2N4 HTS is smaller than the corresponding value of its individual monolayers. The heterostructure structure can enhance the absorption of light spectra not only in the ultraviolet region but also in the visible region as compared to MoSi2N4 and MoS2 monolayers. The refractive index behaviour of the HTS can be described as the cumulative effect which is well described in terms of a combination of the individual effects (the refractive index of MoSi2N4 and MoS2 monolayers). |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000642436200001 |
Publication Date |
2021-03-10 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1144-0546 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.269 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
|
Approved |
Most recent IF: 3.269 |
Call Number |
UA @ admin @ c:irua:178300 |
Serial |
6964 |
Permanent link to this record |
|
|
|
Author |
Faraji, M.; Bafekry, A.; Gogova, D.; Hoat, D.M.; Ghergherehchi, M.; Chuong, N.V.; Feghhi, S.A.H. |
Title |
Novel two-dimensional ZnO₂, CdO₂ and HgO₂ monolayers: a first-principles-based prediction |
Type |
A1 Journal article |
Year |
2021 |
Publication |
New Journal Of Chemistry |
Abbreviated Journal |
New J Chem |
Volume |
45 |
Issue |
|
Pages |
9368-9374 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
In this paper, the existence of monolayers with the chemical formula XO2, where X = Zn, Cd, and Hg with hexagonal and tetragonal lattice structures is theoretically predicted by means of first principles calculations. Through cohesive energy calculation and phonon dispersion simulation, it has been proven that the two-dimensional XO2 monolayers proposed are energetically and dynamically stable suggesting their potential experimental realization. Our detailed study demonstrates that these novel newly predicted materials are half-metals and dilute magnetic semiconductors, and they exhibit magnetism in the ground state. The half-metallic character could find many applications in electronic and spintronic devices. Research into the magnetic properties revealed here can enrich theoretical knowledge in this area and provide more potential candidates for XO2 2D-based materials and van der Waals heterostructures. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000645671700001 |
Publication Date |
2021-04-16 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1144-0546 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.269 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
|
Approved |
Most recent IF: 3.269 |
Call Number |
UA @ admin @ c:irua:178245 |
Serial |
7006 |
Permanent link to this record |
|
|
|
Author |
Afanasov, I.M.; Lebedev, O.I.; Kolozhvary, B.A.; Smirnov, A.V.,; Van Tendeloo, G. |
Title |
Nickel/carbon composite materials based on expanded graphite |
Type |
A1 Journal article |
Year |
2011 |
Publication |
New carbon materials |
Abbreviated Journal |
|
Volume |
26 |
Issue |
5 |
Pages |
335-340 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Monolithic nickel/carbon (Ni/C) composites were prepared from coal tar pitch-impregnated compressed expanded graphite pre-decorated with NiO particles (EGNiO) by pyrolysis at 550 °C and subsequent steam activation at 800 °C. The microstructural arrangement of the Ni-comprising nanoparticles in the composites was investigated using transmission electron microscopy. The specific surface area and porosity of the composites were analyzed by nitrogen adsorption. The catalytic activity of the composites was compared with the material obtained by the conventional H2 treatment of EGNiO using hydrocracking of 2,2,3-trimethylpentane as a model reaction. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000296926500003 |
Publication Date |
2011-11-12 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1872-5805; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
7 |
Open Access |
|
Notes |
Iap |
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:93633 |
Serial |
2340 |
Permanent link to this record |
|
|
|
Author |
Afanasov, I.M.; Van Tendeloo, G.; Mateev, A.T. |
Title |
Production and structure of exfoliated graphite/coke composites modified by ZrO2 nanoparticles |
Type |
A1 Journal article |
Year |
2010 |
Publication |
New carbon materials |
Abbreviated Journal |
|
Volume |
25 |
Issue |
4 |
Pages |
255-260 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Exfoliated graphite/coke composites modified by ZrO2 nanoparticles were produced using two different techniques and characterized by means of X-ray diffraction, scanning and transmission electron microscopy. In the first, low-density exfoliated graphite/coke blocks were dipped repeatedly and alternately in ZrO(NO3)2 and NH4OH solutions and subsequently heat treated at 1200°C in nitrogen to deposit thin layers of ZrO2 nanoparticles on the free surfaces of the carbon matrix. In the second, a mixture of expandable graphite, phenol-formaldehyde resin powder, and ZrOC2O4-modified fibrous cellulose in a sealed container was submitted to thermal shock at 900 °C followed by heat treatment at 1 200 °C in nitrogen to obtain the modified composites. The ZrO2 nanoparticles formed in the second technique were incorporated into the composites in three length scales: 6-30 nm-isolated nanoparticles and small blobs, 200-1000 nm-lengthy dendrite-like structures, and thin layer adhering to the surface of the 1-40 μm long cellulose carbon fibers. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000281534800003 |
Publication Date |
2010-09-02 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1872-5805; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
Iap-Vi |
Approved |
Most recent IF: NA |
Call Number |
UA @ lucian @ c:irua:84438 |
Serial |
2721 |
Permanent link to this record |
|
|
|
Author |
Eisma, D.; Kalf, J.; Karmini, M.; Mook, W.G.; Van Put, A.; Bernard, P.; Van Grieken, R. |
Title |
Dispersal of suspended matter in Makasar Strait and the Flores Basin |
Type |
A1 Journal article |
Year |
1989 |
Publication |
Netherlands journal of sea research |
Abbreviated Journal |
|
Volume |
24 |
Issue |
4 |
Pages |
383-398 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
In November 1984 in Makasar and the Flores Basin water samples were collected (T, S, dissolved O2, total CO2), bottom samples (sediment composition) and suspended matter (particle composition, particle size). A sediment trap was moored in the Flores Basin at 4600 m depth for nearly four months, covering the dry season. In the Flores Basin there are indications for bottom flow resuspending bottom material or preventing suspended material from settling; in Makasar Strait there is probably inflow of deep water both from the south and from the north, resulting in a very slow bottom water flor. Bottom deposits in Makasar Strait and the Flores Basin are predominantly terrigenous, with an admixture of organic carbonate and silica (mostly coccoliths). Volcanic material is primarily present near to the volcanoes in the south and reaches the deeper basins by slumping. In the suspended matter no volcanic particles and little planktonic material were found, although the latter form 10 to 15% of the top sediment and of the material deposited in the sediment trap. In suspension particles with a large concentration of tin (Sn) were found associated mainly with iron. They probably come from northern Kalimantan or northern Sulawesi. Suspended matter concentrations were mainly less than 0.5 mg·dm−3, only off the Mahakam river mouth were concentrations higher than 1 mg·dm−3. Particle size was erratic because of the variable composition of the coarser particles in suspension. Organic matter concentrations in suspension (in mg·dm−3) roughly follow the distribution of total suspended matter but organic content (in %) of the suspended matter does not show any trends. All organic matter in suspension is of marine origin except in the Mahakam river and estuary. Deposition rates, as estimated from the sediment trap results, are 150 mg·cm−2·a−1 for the total sediment, 26 mg·cm−2·a−1 for carbonate and 13 mg·cm−2·a−1 for organic matter. Flocs and fibres in suspension were only found in and below the Mahakam river plume that reaches ca 400 km from the river mouth to the southeast, and in surface waters associated with plankton (diatoms). The formation of these flocs (broken-up macroflocs or marine snow) is primarily related to particle concentration, turbulence, and the presence of organisms that produce sticky material or glue particles together. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
|
Publication Date |
2003-08-07 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0077-7579; 1873-1406 |
ISBN |
|
Additional Links |
UA library record |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ admin @ c:irua:116825 |
Serial |
7814 |
Permanent link to this record |
|
|
|
Author |
Martin, J.-M.; Thomas, A.J.; Van Grieken, R.E. |
Title |
Trace element composition of Zaire suspended sediments |
Type |
A1 Journal article |
Year |
1978 |
Publication |
Netherlands journal of sea research |
Abbreviated Journal |
|
Volume |
12 |
Issue |
3/4 |
Pages |
414-420 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
|
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
|
Publication Date |
2003-08-07 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
0077-7579; 1873-1406 |
ISBN |
|
Additional Links |
UA library record |
Impact Factor |
|
Times cited |
|
Open Access |
|
Notes |
|
Approved |
no |
Call Number |
UA @ admin @ c:irua:116609 |
Serial |
8688 |
Permanent link to this record |
|
|
|
Author |
Johnson, G.; Yang, M.Y.; Liu, C.; Zhou, H.; Zuo, X.; Dickie, D.A.; Wang, S.; Gao, W.; Anaclet, B.; Perras, F.A.; Ma, F.; Zeng, C.; Wang, D.; Bals, S.; Dai, S.; Xu, Z.; Liu, G.; Goddard III, W.A.; Zhang, S. |
Title |
Nanocluster superstructures assembled via surface ligand switching at high temperature |
Type |
A1 Journal article |
Year |
2023 |
Publication |
Nature synthesis |
Abbreviated Journal |
|
Volume |
2 |
Issue |
9 |
Pages |
828-837 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Superstructures with nanoscale building blocks, when coupled with precise control of the constituent units, open opportunities in rationally designing and manufacturing desired functional materials. Yet, synthetic strategies for the large-scale production of superstructures are scarce. We report a scalable and generalized approach to synthesizing superstructures assembled from atomically precise Ce24O28(OH)8 and other rare-earth metal-oxide nanoclusters alongside a detailed description of the self-assembly mechanism. Combining operando small-angle X-ray scattering, ex situ molecular and structural characterizations, and molecular dynamics simulations indicates that a high-temperature ligand-switching mechanism, from oleate to benzoate, governs the formation of the nanocluster assembly. The chemical tuning of surface ligands controls superstructure disassembly and reassembly, and furthermore, enables the synthesis of multicomponent superstructures. This synthetic approach, and the accurate mechanistic understanding, are promising for the preparation of superstructures for use in electronics, plasmonics, magnetics and catalysis. Synthesizing superstructures with precisely controlled nanoscale building blocks is challenging. Here the assembly of superstructures is reported from atomically precise Ce24O28(OH)8 and other rare-earth metal-oxide nanoclusters and their multicomponent combinations. A high-temperature ligand-switching mechanism controls the self-assembly. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
001124824000001 |
Publication Date |
2023-05-01 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
|
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
|
Times cited |
2 |
Open Access |
Not_Open_Access |
Notes |
|
Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:202180 |
Serial |
9060 |
Permanent link to this record |
|
|
|
Author |
Lukyanchuk, I.; Vinokur, V.M.; Rydh, A.; Xie, R.; Milošević, M.V.; Welp, U.; Zach, M.; Xiao, Z.L.; Crabtree, G.W.; Bending, S.J.; Peeters, F.M.; Kwok, W.K. |
Title |
Rayleigh instability of confined vortex droplets in critical superconductors |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Nature physics |
Abbreviated Journal |
Nat Phys |
Volume |
11 |
Issue |
11 |
Pages |
21-25 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Depending on the Ginzburg-Landau parameter kappa, superconductors can either be fully diamagnetic if kappa < 1/root 2 (type I superconductors) or allow magnetic flux to penetrate through Abrikosov vortices if kappa > 1/root 2 (type II superconductors; refs 1,2). At the Bogomolny critical point, kappa = kappa(c) = 1/root 2, a state that is infinitely degenerate with respect to vortex spatial configurations arises(3,4). Despite in-depth investigations of conventional type I and type II superconductors, a thorough understanding of the magnetic behaviour in the near-Bogomolny critical regime at kappa similar to kappa(c) remains lacking. Here we report that in confined systems the critical regime expands over a finite interval of kappa forming a critical superconducting state. We show that in this state, in a sample with dimensions comparable to the vortex core size, vortices merge into a multi-quanta droplet, which undergoes Rayleigh instability(5) on increasing kappa and decays by emitting single vortices. Superconducting vortices realize Nielsen-Olesen singular solutions of the Abelian Higgs model, which is pervasive in phenomena ranging from quantum electrodynamics to cosmology(6-9). Our study of the transient dynamics of Abrikosov-Nielsen-Olesen vortices in systems with boundaries promises access to non-trivial effects in quantum field theory by means of bench-top laboratory experiments. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000346831100018 |
Publication Date |
2014-11-06 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1745-2473;1745-2481; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
22.806 |
Times cited |
20 |
Open Access |
|
Notes |
; We would like to thank N. Nekrasov for illuminating discussions. The work was supported by the US Department of Energy, Office of Science Materials Sciences and Engineering Division (V.M.V., W.K.K., U.W., R.X., M.Z., Z.L.X., G.W.C. and partially I.L. through the Materials Theory Institute), by FP7-IRSES-SIMTECH and ITN-NOTEDEV programs (I.L.), and by the Flemish Science Foundation (FWO-Vlaanderen) (M.V.M. and F.M.P.). ; |
Approved |
Most recent IF: 22.806; 2015 IF: 20.147 |
Call Number |
c:irua:122791 c:irua:122791 |
Serial |
2815 |
Permanent link to this record |
|
|
|
Author |
Roditchev, D.; Brun, C.; Serrier-Garcia, L.; Cuevas, J.C.; Bessa, V.H.L.; Milošević, M.V.; Debontridder, F.; Stolyarov, V.; Cren, T. |
Title |
Direct observation of Josephson vortex cores |
Type |
A1 Journal article |
Year |
2015 |
Publication |
Nature physics |
Abbreviated Journal |
Nat Phys |
Volume |
11 |
Issue |
11 |
Pages |
332-337 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Superconducting correlations may propagate between two superconductors separated by a tiny insulating or metallic barrier, allowing a dissipationless electric current to flow(1,2). In the presence of a magnetic field, the maximum supercurrent oscillates(3) and each oscillation corresponding to the entry of one Josephson vortex into the barrier(4). Josephson vortices are conceptual blocks of advanced quantum devices such as coherent terahertz generators(5) or qubits for quantum computing(6), in which on-demand generation and control is crucial. Here, we map superconducting correlations inside proximity Josephson junctions(7) using scanning tunnelling microscopy. Unexpectedly, we find that such Josephson vortices have real cores, in which the proximity gap is locally suppressed and the normal state recovered. By following the Josephson vortex formation and evolution we demonstrate that they originate from quantum interference of Andreev quasiparticles(8), and that the phase portraits of the two superconducting quantum condensates at edges of the junction decide their generation, shape, spatial extent and arrangement. Our observation opens a pathway towards the generation and control of Josephson vortices by applying supercurrents through the superconducting leads of the junctions, that is, by purely electrical means without any need for a magnetic field, which is a crucial step towards high-density on-chip integration of superconducting quantum devices. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000352163100016 |
Publication Date |
2015-02-23 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1745-2473;1745-2481; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
22.806 |
Times cited |
102 |
Open Access |
|
Notes |
T.C., C.B., F.D., V.S. and D.R. acknowledge financial support from the French ANR project and the French-Russian program PICS-CNRS/RAS. The authors also thank V. Cherkez for assistance during experiments and V. Vinokur (Argonne National Laboratory, Illinois USA) and A. Buzdin (University of Bordeaux 1, France) for stimulating discussions. J.C.C. acknowledges financial support from the Spanish MICINN (Contract No. FIS2011-28851-C1). V.H.L.B. acknowledges support from CNPq Brazil and productive discussions with Prof. A. Chaves (UFC, Brazil). M.V.M. acknowledges support from Research Foundation Flanders (FWO-Vlaanderen) and CAPES Brazil (PVE project BEX1392/11-5). |
Approved |
Most recent IF: 22.806; 2015 IF: 20.147 |
Call Number |
c:irua:132524 c:irua:132524 |
Serial |
3943 |
Permanent link to this record |
|
|
|
Author |
Mao, J.; Jiang, Y.; Moldovan, D.; Li, G.; Watanabe, K.; Taniguchi, T.; Masir, M.R.; Peeters, F.M.; Andrei, E.Y. |
Title |
Realization of a tunable artificial atom at a supercritically charged vacancy in graphene |
Type |
A1 Journal article |
Year |
2016 |
Publication |
Nature physics |
Abbreviated Journal |
Nat Phys |
Volume |
12 |
Issue |
12 |
Pages |
545-549 |
Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
Abstract |
Graphene’s remarkable electronic properties have fuelled the vision of a graphene-based platform for lighter, faster and smarter electronics and computing applications. One of the challenges is to devise ways to tailor graphene’s electronic properties and to control its charge carriers. Here we show that a single-atom vacancy in graphene can stably host a local charge and that this charge can be gradually built up by applying voltage pulses with the tip of a scanning tunnelling microscope. The response of the conduction electrons in graphene to the local charge is monitored with scanning tunnelling and Landau level spectroscopy, and compared to numerical simulations. As the charge is increased, its interaction with the conduction electrons undergoes a transition into a supercritical regime where itinerant electrons are trapped in a sequence of quasi-bound states which resemble an artificial atom. The quasi-bound electron states are detected by a strong enhancement of the density of states within a disc centred on the vacancy site which is surrounded by halo of hole states. We further show that the quasi-bound states at the vacancy site are gate tunable and that the trapping mechanism can be turned on and off, providing a mechanism to control and guide electrons in graphene. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000377475700011 |
Publication Date |
2016-02-22 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1745-2473 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
22.806 |
Times cited |
93 |
Open Access |
|
Notes |
; Funding was provided by DOE-FG02-99ER45742 (STM/STS), NSF DMR 1207108 (fabrication and characterization). Theoretical work supported by ESF-EUROCORES-EuroGRAPHENE, FWO-VI and Methusalem programme of the Flemish government. We thank V. F. Libisch, M. Pereira and E. Rossi for useful discussions. ; |
Approved |
Most recent IF: 22.806 |
Call Number |
c:irua:134210 |
Serial |
4011 |
Permanent link to this record |
|
|
|
Author |
Wang, D.; Dasgupta, T.; van der Wee, E.B.; Zanaga, D.; Altantzis, T.; Wu, Y.; Coli, G.M.; Murray, C.B.; Bals, S.; Dijkstra, M.; van Blaaderen, A. |
Title |
Binary icosahedral clusters of hard spheres in spherical confinement |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Nature Physics |
Abbreviated Journal |
Nat Phys |
Volume |
|
Issue |
|
Pages |
1-9 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Applied Electrochemistry & Catalysis (ELCAT) |
Abstract |
The influence of geometry on the local and global packing of particles is important to many fundamental and applied research themes, such as the structure and stability of liquids, crystals and glasses. Here we show by experiments and simulations that a binary mixture of hard-sphere-like nanoparticles crystallizing into a MgZn(2)Laves phase in bulk spontaneously forms icosahedral clusters in slowly drying droplets. Using advanced electron tomography, we are able to obtain the real-space coordinates of all the spheres in the icosahedral clusters of up to about 10,000 particles. The local structure of 70-80% of the particles became similar to that of the MgCu(2)Laves phase. These observations are important for photonic applications. In addition, we observed in simulations that the icosahedral clusters nucleated away from the spherical boundary, which is distinctly different from that of the single species clusters. Our findings open the way for particle-level studies of nucleation and growth of icosahedral clusters, and of binary crystallization. The authors investigate out-of-equilibrium crystallization of a binary mixture of sphere-like nanoparticles in small droplets. They observe the spontaneous formation of an icosahedral structure with stable MgCu(2)phases, which are promising for photonic applications. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000564497300002 |
Publication Date |
2020-08-31 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1745-2473; 1745-2481 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
19.6 |
Times cited |
38 |
Open Access |
OpenAccess |
Notes |
; D.W., E.B.v.d.W. and A.v.B. acknowledge partial financial support from the European Research Council under the European Union's Seventh Framework Programme (FP-2007-2013)/ERC Advanced Grant Agreement 291667 HierarSACol. T.D. and M. D. acknowledge financial support from the Industrial Partnership Programme, 'Computational Sciences for Energy Research' (grant number 13CSER025), of the Netherlands Organization for Scientific Research (NWO), which was co-financed by Shell Global Solutions International BV G.M.C. was also financially supported by NWO. S.B. acknowledges financial support from ERC Consolidator Grant Number 815128 REALNANO. T.A. acknowledges a post-doctoral grant from the Research Foundation Flanders (FWO, Belgium). C.B.M. and Y.W. acknowledge support for materials synthesis from the Office of Naval Research Multidisciplinary University Research Initiative Award ONR N00014-18-1-2497. G. A. Blab is gratefully acknowledged for 3D printing numerous truncated tetrahedra, which increased our understanding of the connection between the binary icosahedral cluster and Laves phase structures. N. Tasios is sincerely thanked for providing the code for the diffraction pattern calculation. M. Hermes is sincerely thanked for providing interactive views of the structures in this work. We thank G. van Tendeloo, M. Engel, J. Wang, S. Dussi, L. Filion, E. Boattini, S. Paliwal, N. Tasios, B. van der Meer, I. Lobato, J. Wu and L. Laurens for fruitful discussions. We acknowledge the EM Square centre at Utrecht University for the access to the microscopes. ; sygma |
Approved |
Most recent IF: 19.6; 2020 IF: 22.806 |
Call Number |
UA @ admin @ c:irua:172044 |
Serial |
6460 |
Permanent link to this record |
|
|
|
Author |
Godefroo, S.; Hayne, M.; Jivanescu, M.; Stesmans, A.; Zacharias, M.; Lebedev, O.I.; Van Tendeloo, G.; Moshchalkov, V.V. |
Title |
Classification and control of the origin of photoluminescence from Si nanocrystals |
Type |
A1 Journal article |
Year |
2008 |
Publication |
Nature nanotechnology |
Abbreviated Journal |
Nat Nanotechnol |
Volume |
3 |
Issue |
3 |
Pages |
174-178 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
Abstract |
Silicon dominates the electronics industry, but its poor optical properties mean that III-V compound semiconductors are preferred for photonics applications. Photoluminescence at visible wavelengths was observed from porous Si at room temperature in 1990, but the origin of these photons (do they arise from highly localized defect states or quantum confinement effects?) has been the subject of intense debate ever since. Attention has subsequently shifted from porous Si to Si nanocrystals, but the same fundamental question about the origin of the photoluminescence has remained. Here we show, based on measurements in high magnetic fields, that defects are the dominant source of light from Si nanocrystals. Moreover, we show that it is possible to control the origin of the photoluminescence in a single sample: passivation with hydrogen removes the defects, resulting in photoluminescence from quantum-confined states, but subsequent ultraviolet illumination reintroduces the defects, making them the origin of the light again. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000254743600017 |
Publication Date |
2008-03-02 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1748-3387;1748-3395; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
38.986 |
Times cited |
426 |
Open Access |
|
Notes |
Fwo |
Approved |
Most recent IF: 38.986; 2008 IF: 20.571 |
Call Number |
UA @ lucian @ c:irua:102630 |
Serial |
373 |
Permanent link to this record |
|
|
|
Author |
Talgorn, E.; Gao, Y.; Aerts, M.; Kunneman, L.T.; Schins, J.M.; Savenije, T.J.; van Huis, M.A.; van der Zant, H.S.J.; Houtepen, A.J.; Siebbeles, L.D.A. |
Title |
Unity quantum yield of photogenerated charges and band-like transport in quantum-dot solids |
Type |
A1 Journal article |
Year |
2011 |
Publication |
Nature nanotechnology |
Abbreviated Journal |
Nat Nanotechnol |
Volume |
6 |
Issue |
11 |
Pages |
733-739 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
Solid films of colloidal quantum dots show promise in the manufacture of photodetectors and solar cells. These devices require high yields of photogenerated charges and high carrier mobilities, which are difficult to achieve in quantum-dot films owing to a strong electronhole interaction and quantum confinement. Here, we show that the quantum yield of photogenerated charges in strongly coupled PbSe quantum-dot films is unity over a large temperature range. At high photoexcitation density, a transition takes place from hopping between localized states to band-like transport. These strongly coupled quantum-dot films have electrical properties that approach those of crystalline bulk semiconductors, while retaining the size tunability and cheap processing properties of colloidal quantum dots. |
Address |
|
Corporate Author |
|
Thesis |
|
Publisher |
|
Place of Publication |
|
Editor |
|
Language |
|
Wos |
000296737300012 |
Publication Date |
2011-09-25 |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
Series Volume |
|
Series Issue |
|
Edition |
|
ISSN |
1748-3387;1748-3395; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
38.986 |
Times cited |
129 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 38.986; 2011 IF: 27.270 |
Call Number |
UA @ lucian @ c:irua:93296 |
Serial |
3813 |
Permanent link to this record |