| Records |
| Author |
Salman, O.U.; Finel, A.; Delville, R.; Schryvers, D. |
| Title |
The role of phase compatibility in martensite |
Type |
A1 Journal article |
Year  |
2012 |
Publication |
Journal of applied physics
T2 – 22nd International Symposium on Integrated Functionalities (ISIF), JUN 13-16, 2010, San Juan, PR |
Abbreviated Journal |
J Appl Phys |
| Volume |
111 |
Issue |
10 |
Pages |
103517 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Shape memory alloys inherit their macroscopic properties from their mesoscale microstructure originated from the martensitic phase transformation. In a cubic to orthorhombic transition, a single variant of martensite can have a compatible (exact) interface with the austenite for some special lattice parameters in contrast to conventional austenite/twinned martensite interface with a transition layer. Experimentally, the phase compatibility results in a dramatic drop in thermal hysteresis and gives rise to very stable functional properties over cycling. Here, we investigate the microstructures observed in Ti50Ni50-xPdx alloys that undergo a cubic to orthorhombic martensitic transformation using a three-dimensional phase field approach. We will show that the simulation results are in very good agreement with transmission electron microscopy observations. However, the understanding of the drop in thermal hysteresis requires the coupling of phase transformation with plastic activity. We will discuss this point within the framework of thermoelasticity, which is a generic feature of the martensitic transformation. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4712629] |
| Address |
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| Corporate Author |
|
Thesis |
|
| Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
| Language |
|
Wos |
000305363700053 |
Publication Date |
2012-05-21 |
| 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 |
11 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 2.068; 2012 IF: 2.210 |
| Call Number |
UA @ lucian @ c:irua:100310 |
Serial |
2919 |
| Permanent link to this record |
| |
|
| |
| Author |
Phung, Q.M.; Vancoillie, S.; Delabie, A.; Pourtois, G.; Pierloot, K. |
| Title |
Ruthenocene and cyclopentadienyl pyrrolyl ruthenium as precursors for ruthenium atomic layer deposition : a comparative study of dissociation enthalpies |
Type |
A1 Journal article |
| Year |
2012 |
Publication |
Theoretical chemistry accounts : theory, computation, and modeling |
Abbreviated Journal |
Theor Chem Acc |
| Volume |
131 |
Issue |
7 |
Pages |
1238 |
| Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| Abstract |
RuCp2 (ruthenocene) and RuCpPy (cyclopentadienyl pyrrolyl ruthenium) complexes are used in ruthenium (Ru) atomic layer deposition (ALD) but exhibit a markedly different reactivity with respect to the substrate and co-reactant. In search of an explanation, we report here the results of a comparative study of the heterolytic and homolytic dissociation enthalpy of these two ruthenium complexes, making use of either density functional theory (DFT) or multiconfigurational perturbation theory (CASPT2). While both methods predict distinctly different absolute dissociation enthalpies, they agree on the relative values between both molecules. A reduced heterolytic dissociation enthalpy is obtained for RuCpPy compared to RuCp2, although the difference obtained from CASPT2 (19.9 kcal/mol) is slightly larger than the one obtained with any of the DFT functionals (around 17 kcal/mol). Both methods also agree on the more pronounced stability of the Cp- ligand in RuCpPy than in RuCp2 (by around 9 kcal/mol with DFT and by 6 kcal/mol with CASPT2). |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000307274300003 |
Publication Date |
2012-07-07 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1432-881X;1432-2234; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
1.89 |
Times cited |
5 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 1.89; 2012 IF: 2.233 |
| Call Number |
UA @ lucian @ c:irua:101139 |
Serial |
2935 |
| Permanent link to this record |
| |
|
| |
| Author |
Matulis, A.; Masir, M.R.; Peeters, F.M. |
| Title |
Scattering of a Dirac electron on a mass barrier |
Type |
A1 Journal article |
| Year |
2012 |
Publication |
Physical review : A : atomic, molecular and optical physics |
Abbreviated Journal |
Phys Rev A |
| Volume |
86 |
Issue |
2 |
Pages |
022101 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
The interaction of a wave packet (and in particular the wave front) with a mass barrier is investigated in one dimension. We discuss the main features of the wave packet that are inherent to two-dimensional wave packets, such as compression during reflection, penetration in the case when the energy is lower than the height of the barrier, waving tails, precursors, and the retardation of the reflected and penetrated wave packets. These features depend on the wave-packet envelope function which we demonstrate by considering the case of a rectangular wave packet with sharp front and trailing edges and a smooth Gaussian wave packet. The method of Fourier integral for obtaining the nonstationary solutions is used. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
| Language |
|
Wos |
000306991200001 |
Publication Date |
2012-08-01 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1050-2947;1094-1622; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.925 |
Times cited |
9 |
Open Access |
|
| Notes |
; This research was supported by the Flemish Science Foundation (FWO-Vl) and (in part) by the Lithuanian Science Council under Project No. MIP-79/2010. ; |
Approved |
Most recent IF: 2.925; 2012 IF: 3.042 |
| Call Number |
UA @ lucian @ c:irua:100822 |
Serial |
2948 |
| Permanent link to this record |
| |
|
| |
| Author |
Angelomé, P.C.; Heidari Mezerji, H.; Goris, B.; Pastoriza-Santos, I.; Pérez-Juste, J.; Bals, S.; Liz-Marzán, L.M. |
| Title |
Seedless synthesis of single crystalline Au nanoparticles with unusual shapes and tunable LSPR in the near-IR |
Type |
A1 Journal article |
| Year |
2012 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
| Volume |
24 |
Issue |
7 |
Pages |
1393-1399 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
The plasmonic properties of metal nanoparticles have acquired great importance because of their potential applications in very diverse fields. Metal nanoparticles with localized surface plasmon resonances (LSPR) in the near-infrared (NIR, 7501300 nm) are of particular interest because tissues, blood, and water display low absorption in this spectral range, thus facilitating biomedical applications. Cetyltrimethylammonium chloride (CTAC) was used to induce the seedless formation of highly anisotropic, twisted single crystalline Au nanoparticles in a single step. The LSPR of the obtained particles can be tuned from 600 nm up to 1400 nm by simply changing the reaction temperature or the reagents concentrations. The tunability of the LSPR is closely associated with significant changes in the final particle morphology, which was studied by advanced electron microscopy techniques (3D Tomography and HAADF-STEM). Kinetic experiments were carried out to establish the growth mechanism, suggesting that slow kinetics together with the complexation of the gold salt precursor to CTAC are key factors favoring the formation of these anisotropic particles. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
| Language |
|
Wos |
000302487500020 |
Publication Date |
2012-03-16 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0897-4756;1520-5002; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
9.466 |
Times cited |
42 |
Open Access |
|
| Notes |
Fwo |
Approved |
Most recent IF: 9.466; 2012 IF: 8.238 |
| Call Number |
UA @ lucian @ c:irua:97388 |
Serial |
2959 |
| Permanent link to this record |
| |
|
| |
| Author |
Khalilov, U.; Pourtois, G.; van Duin, A.C.T.; Neyts, E.C. |
| Title |
Self-limiting oxidation in small-diameter Si nanowires |
Type |
A1 Journal article |
| Year |
2012 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
| Volume |
24 |
Issue |
11 |
Pages |
2141-2147 |
| Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| Abstract |
Recently, core shell silicon nanowires (Si-NWs) have been envisaged to be used for field-effect transistors and photovoltaic applications. In spite of the constant downsizing of such devices, the formation of ultrasmall diameter core shell Si-NWs currently remains entirely unexplored. We report here on the modeling of the formation of such core shell Si-NWs using a dry thermal oxidation of 2 nm diameter (100) Si nanowires at 300 and 1273 K, by means of reactive molecular dynamics simulations using the ReaxFF potential. Two different oxidation mechanisms are discussed, namely a self-limiting process that occurs at low temperature (300 K), resulting in a Si core I ultrathin SiO2 silica shell nanowire, and a complete oxidation process that takes place at a higher temperature (1273 K), resulting in the formation of an ultrathin SiO2 silica nanowire. The oxidation kinetics of both cases and the resulting structures are analyzed in detail. Our results demonstrate that precise control over the Si-core radius of such NWs and the SiOx (x <= 2.0) oxide shell is possible by controlling the growth temperature used during the oxidation process. |
| Address |
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| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
| Language |
|
Wos |
000305092600021 |
Publication Date |
2012-05-18 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0897-4756;1520-5002; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
9.466 |
Times cited |
45 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 9.466; 2012 IF: 8.238 |
| Call Number |
UA @ lucian @ c:irua:99079 |
Serial |
2976 |
| Permanent link to this record |
| |
|
| |
| Author |
Zhang, Q.-Z.; Zhao, S.-X.; Jiang, W.; Wang, Y.-N. |
| Title |
Separate control between geometrical and electrical asymmetry effects in capacitively coupled plasmas |
Type |
A1 Journal article |
| Year |
2012 |
Publication |
Journal of physics: D: applied physics |
Abbreviated Journal |
J Phys D Appl Phys |
| Volume |
45 |
Issue |
30 |
Pages |
305203 |
| Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| Abstract |
Both geometrical and electrical asymmetry effects in capacitive argon discharges are investigated using a two-dimensional particle-in-cell coupled with Monte Carlo collision model. When changing the ratio of the top and bottom electrode surface areas and the phase shift between the two applied harmonics, the induced self-bias was found to develop separately. By adjusting the ratio between the high and low harmonic amplitudes, the electrical asymmetry effect at a fixed phase shift can be substantially optimized. However, the self-bias caused by the geometrical asymmetry hardly changed. Moreover, the separate control of these two asymmetry effects can also be demonstrated from their power absorption profiles. Both the axial and radial plasma density distributions can be modulated by the electrical asymmetry effect. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
London |
Editor |
|
| Language |
|
Wos |
000306475200007 |
Publication Date |
2012-07-10 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0022-3727;1361-6463; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.588 |
Times cited |
20 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 2.588; 2012 IF: 2.528 |
| Call Number |
UA @ lucian @ c:irua:100751 |
Serial |
2984 |
| Permanent link to this record |
| |
|
| |
| Author |
Djotyan, A.P.; Avetisyan, A.A.; Hao, Y.L.; Peeters, F.M. |
| Title |
Shallow donor near a semiconductor surface in the presence of locally spherical scanning tunneling microscope tip |
Type |
P1 Proceeding |
| Year |
2012 |
Publication |
Proceedings of the Society of Photo-optical Instrumentation Engineers
T2 – Conference on Photonics and Micro and Nano-structured Materials, JUN 28-30, 2011, Yerevan, ARMENIA |
Abbreviated Journal |
|
| Volume |
|
Issue |
|
Pages |
84140-84148 |
| Keywords |
P1 Proceeding; Engineering sciences. Technology; Condensed Matter Theory (CMT) |
| Abstract |
We developed a variational approach to investigate the ground state energy and the extend of the wavefunction of a neutral donor located near a semiconductor surface in the presence of scanning tunneling microscope (STM) metallic tip. We apply the effective mass approximation and use a variational wavefunction that takes into account the influence of all image charges that arise due to the presence of a metallic tip. The behavior of the ground state energy when the tip approaches the semiconductor surface is investigated. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000303856600020 |
Publication Date |
2012-01-20 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
8414 |
Series Issue |
|
Edition |
|
| ISSN |
|
ISBN |
|
Additional Links |
UA library record; WoS full record |
| Impact Factor |
|
Times cited |
|
Open Access |
|
| Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl), and the Belgian Science Policy. One of us (AAA) was supported by a fellowship from the Belgian Federal Science Policy Office (Belspo). ; |
Approved |
Most recent IF: NA |
| Call Number |
UA @ lucian @ c:irua:113047 |
Serial |
2987 |
| Permanent link to this record |
| |
|
| |
| Author |
Tsirlin, A.A.; Abakumov, A.M.; Ritter, C.; Henry, P.F.; Janson, O.; Rosner, H. |
| Title |
Short-range order of Br and three-dimensional magnetism in (CuBr)LaNb2O7 |
Type |
A1 Journal article |
| Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| Volume |
85 |
Issue |
21 |
Pages |
214427 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
We present a comprehensive study of the crystal structure, magnetic structure, and microscopic magnetic model of (CuBr)LaNb2O7, the Br analog of the spin-gap quantum magnet (CuCl) LaNb2O7. Despite similar crystal structures and spin lattices, the magnetic behavior and even peculiarities of the atomic arrangement in the Cl and Br compounds are very different. The high- resolution x-ray and neutron data reveal a split position of Br atoms in (CuBr) LaNb2O7. This splitting originates from two possible configurations developed by [CuBr] zigzag ribbons. While the Br atoms are locally ordered in the ab plane, their arrangement along the c direction remains partially disordered. The predominant and energetically more favorable configuration features an additional doubling of the c lattice parameter that was not observed in (CuCl) LaNb2O7. (CuBr) LaNb2O7 undergoes long-range antiferromagnetic ordering at T-N = 32 K, which is nearly 70% of the leading exchange coupling J4 similar or equal to 48 K. The Br compound does not show any experimental signatures of low-dimensional magnetism because the underlying spin lattice is three-dimensional. The coupling along the c direction is comparable to the couplings in the ab plane, even though the shortest Cu-Cu distance along c (11.69 angstrom) is three times larger than nearest-neighbor distances in the ab plane (3.55 angstrom). The stripe antiferromagnetic long-range order featuring columns of parallel spins in the ab plane and antiparallel spins along c is verified experimentally and confirmed by the microscopic analysis. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000305557600002 |
Publication Date |
2012-06-22 |
| 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 |
|
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
| Call Number |
UA @ lucian @ c:irua:100289 |
Serial |
2998 |
| Permanent link to this record |
| |
|
| |
| Author |
Quintana, M.; Grzelczak, M.; Spyrou, K.; Calvaresi, M.; Bals, S.; Kooi, B.; Van Tendeloo, G.; Rudolf, P.; Zerbetto, F.; Prato, M. |
| Title |
A simple road for the transformation of few-layer graphene into MWNTs |
Type |
A1 Journal article |
| Year |
2012 |
Publication |
Journal of the American Chemical Society |
Abbreviated Journal |
J Am Chem Soc |
| Volume |
134 |
Issue |
32 |
Pages |
13310-13315 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
We report the direct formation of multiwalled carbon nanotubes (MWNT) by ultrasonication of graphite in dimethylformamide (DMF) upon addition of ferrocene aldehyde (Fc-CHO). The tubular structures appear exclusively at the edges of graphene layers and contain Fe clusters. Pc in conjunction with benzyl aldehyde, or other Fc derivatives, does not induce formation of NT. Higher amounts of Fc-CHO added to the dispersion do not increase significantly MWNT formation. Increasing the temperature reduces the amount of formation of MWNTs and shows the key role of ultrasound-induced cavitation energy. It is concluded that Fc-CHO first reduces the concentration of radical reactive species that slice graphene into small moieties, localizes itself at the edges of graphene, templates the rolling up of a sheet to form a nanoscroll, where it remains trapped, and finally accepts and donates unpaired electron to the graphene edges and converts the less stable scroll into a MWNT. This new methodology matches the long held notion that CNTs are rolled up graphene layers. The proposed mechanism is general and will lead to control the production of carbon nanostructures by simple ultrasonication treatments. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
| Language |
|
Wos |
000307487200034 |
Publication Date |
2012-05-08 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0002-7863;1520-5126; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
13.858 |
Times cited |
56 |
Open Access |
|
| Notes |
This work was supported by the University of Trieste, the Italian Ministry of Education MIUR (cofin Prot. 20085M27SS), the European Union through the ERC grant No. 246791 – COUNTATOMS, the grant agreement for an Integrated Infrastructure Initiative N. 262348 ESMI, and the “Graphene-based electronics” research program of the Foundation for Fundamental Research on Matter (FOM). |
Approved |
Most recent IF: 13.858; 2012 IF: 10.677 |
| Call Number |
UA @ lucian @ c:irua:101109 |
Serial |
3003 |
| Permanent link to this record |
| |
|
| |
| Author |
Euán-Díaz, E.C.; Misko, V.R.; Peeters, F.M.; Herrera-Velarde, S.; Castaneda-Priego, R. |
| Title |
Single-file diffusion in periodic energy landscapes : the role of hydrodynamic interactions |
Type |
A1 Journal article |
| Year |
2012 |
Publication |
Physical review : E : statistical, nonlinear, and soft matter physics |
Abbreviated Journal |
Phys Rev E |
| Volume |
86 |
Issue |
3Part 1 |
Pages |
031123 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
We report on the dynamical properties of interacting colloids confined to one dimension and subjected to external periodic energy landscapes. We particularly focus on the influence of hydrodynamic interactions on the mean-square displacement. Using Brownian dynamics simulations, we study colloidal systems with two types of repulsive interparticle interactions, namely, Yukawa and superparamagnetic potentials. We find that in the homogeneous case, hydrodynamic interactions lead to an enhancement of the particle mobility and the mean-square displacement at long times scales as t(alpha), with alpha = 1/2 + epsilon and epsilon being a small correction. This correction, however, becomes much more important in the presence of an external field, which breaks the homogeneity of the particle distribution along the line and, therefore, promotes a richer dynamical scenario due to the hydrodynamical coupling among particles. We provide here the complete dynamical scenario in terms of the external potential parameters: amplitude and commensurability. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
American Institute of Physics |
Place of Publication |
Woodbury (NY) |
Editor |
|
| Language |
|
Wos |
000308873500002 |
Publication Date |
2012-09-21 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1539-3755;1550-2376; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.366 |
Times cited |
14 |
Open Access |
|
| Notes |
; This work was partially supported by the “Odysseus” Program of the Flemish Government, the Flemish Science Foundation (FWO-Vl), and PIFI 3.4-PROMEP and CONACyT (Grant Nos. 61418/2007 and 102339/2008, Ph.D. Scholarship No. 230171/ 2010). ; |
Approved |
Most recent IF: 2.366; 2012 IF: 2.313 |
| Call Number |
UA @ lucian @ c:irua:101840 |
Serial |
3021 |
| Permanent link to this record |
| |
|
| |
| Author |
Turner, S.; Egoavil, R.; Batuk, M.; Abakumov, A.A.; Hadermann, J.; Verbeeck, J.; Van Tendeloo, G. |
| Title |
Site-specific mapping of transition metal oxygen coordination in complex oxides |
Type |
A1 Journal article |
| Year |
2012 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
| Volume |
101 |
Issue |
24 |
Pages |
241910 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
We demonstrate site-specific mapping of the oxygen coordination number for transition metals in complex oxides using atomically resolved electron energy-loss spectroscopy in an aberration-corrected scanning transmission electron microscope. Pb2Sr2Bi2Fe6O16 contains iron with a constant Fe3+ valency in both octahedral and tetragonal pyramidal coordination and is selected to demonstrate the principle of site-specific coordination mapping. Analysis of the site-specific Fe-L2,3 data reveals distinct variations in the fine structure that are attributed to Fe in a six-fold (octahedron) or five-fold (distorted tetragonal pyramid) oxygen coordination. Using these variations, atomic resolution coordination maps are generated that are in excellent agreement with simulations. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
| Language |
|
Wos |
000312490000035 |
Publication Date |
2012-12-12 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0003-6951; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.411 |
Times cited |
12 |
Open Access |
|
| Notes |
Fwo; Countatoms; Vortex; Esteem 312483; esteem2jra3 ECASJO; |
Approved |
Most recent IF: 3.411; 2012 IF: 3.794 |
| Call Number |
UA @ lucian @ c:irua:105302UA @ admin @ c:irua:105302 |
Serial |
3030 |
| Permanent link to this record |
| |
|
| |
| Author |
De Trizio, L.; Figuerola, A.; Manna, L.; Genovese, A.; George, C.; Brescia, R.; Saghi, Z.; Simonutti, R.; van Huis, M.; Falqui, A. |
| Title |
Size-tunable, hexagonal plate-like Cu3P and Janus-like Cu-Cu3P nanocrystals |
Type |
A1 Journal article |
| Year |
2012 |
Publication |
ACS nano |
Abbreviated Journal |
Acs Nano |
| Volume |
6 |
Issue |
1 |
Pages |
32-41 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
| Abstract |
We describe two synthesis approaches to colloidal Cu3P nanocrystals using trioctylphosphine (TOP) as phosphorus precursor. One approach is based on the homogeneous nucleation of small Cu3P nanocrystals with hexagonal plate-like morphology and with sizes that can be tuned from 5 to 50 nm depending on the reaction time. In the other approach, metallic Cu nanocrystals are nucleated first and then they are progressively phosphorized to Cu3P. In this case, intermediate Janus-like dimeric nanoparticles can be isolated, which are made of two domains of different materials, Cu and Cu3P, sharing a flat epitaxial interface. The Janus-like nanoparticles can be transformed back to single-crystalline copper particles if they are annealed at high temperature under high vacuum conditions, which makes them an interesting source of phosphorus. The features of the Cu Cu3P Janus-like nanoparticles are compared with those of the Wiped microstructure discovered more than two decades ago in the rapidly quenched Cu Cu3P eutectic of the Cu P alloy, suggesting that other alloy/eutectic systems that display similar behavior might give origin to nanostructures with flat, epitaxial Interface between domains of two diverse materials. Finally, the electrochemical properties of the copper phosphide plates are studied, and they are found to be capable of undergoing lithiation/delithiation through a displacement reaction, while the Janus-like Cu Cu3P particles do not display an electrochemical behavior that would make them suitable for applications in batteries. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000299368300006 |
Publication Date |
2011-12-03 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1936-0851;1936-086X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
13.942 |
Times cited |
60 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 13.942; 2012 IF: 12.062 |
| Call Number |
UA @ lucian @ c:irua:99172 |
Serial |
3039 |
| Permanent link to this record |
| |
|
| |
| Author |
Tempère, J.; Vermeyen, E.; Van Duppen, B. |
| Title |
Skyrmion rows, vortex rows, and phase slip lines in sheared multi-component condensates |
Type |
A1 Journal article |
| Year |
2012 |
Publication |
Physica: C : superconductivity |
Abbreviated Journal |
Physica C |
| Volume |
479 |
Issue |
|
Pages |
61-64 |
| Keywords |
A1 Journal article; Theory of quantum systems and complex systems; Condensed Matter Theory (CMT) |
| Abstract |
When a condensate is sheared by imparting a velocity to a part of the condensate, phase singularities must appear at the interface between the region that is still at rest and the region that has acquired a velocity. For helium, Feynman argued that these phase singularies will arrange themselves in the form of a vortex row. BoseEinstein condensates of ultracold atomic gases differ from helium in that the healing length is generally much larger and is, in fact, tunable. Another difference is that multicomponent condensates can be created, where the two components forming the mixture are usually two different hyperfine states of the condensed atoms. These two components can be manipulated separately and can be interconverted. In this contribution, we investigate how these additional degrees of freedom, available in quantum gases, change what happens in sheared condensates. In particular, we consider skyrmion rows as an alternative to vortex rows, and we also consider phase slip lines filled with the second, unmoving component, in a condensate mixture. We show that depending on the ratios of the interaction strengths between the components, and depending on the shear velocity, skyrmion rows and phase slip lines can become lower in energy than vortex rows, and hence should be observable in quantum gases. Moreover, we find that the velocity field affects the stability region of the condensate with respect to phase separation. |
| Address |
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| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
| Language |
|
Wos |
000308580600013 |
Publication Date |
2012-02-14 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0921-4534; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
1.404 |
Times cited |
1 |
Open Access |
|
| Notes |
; This work was supported by the Research Foundation – Flanders (FWO) through Projects G.0356.06, G.0370.09 N, G.0180.09 N, and G.0365.08. E. V. acknowledges financial support in the form of a Ph.D. fellowship of the Research Foundation – Flanders (FWO). ; |
Approved |
Most recent IF: 1.404; 2012 IF: 0.718 |
| Call Number |
UA @ lucian @ c:irua:100617 |
Serial |
3040 |
| Permanent link to this record |
| |
|
| |
| Author |
Barbier, M.; Papp, G.; Peeters, F.M. |
| Title |
Snake states and Klein tunneling in a graphene Hall bar with a pn-junction |
Type |
A1 Journal article |
| Year |
2012 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
| Volume |
100 |
Issue |
16 |
Pages |
163121-163121,3 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
The Hall (R-H) and bend (R-B) resistances of a graphene Hall bar structure containing a pn-junction are calculated when in the ballistic regime. The simulations are done using the billiard model. Introducing a pn-junction-dividing the Hall bar geometry in two regions-leads to two distinct regimes exhibiting very different physics: (1) both regions are of n-type and (2) one region is n-type and the other p-type. In regime (1), a “Hall plateau”-an enhancement of the resistance-appears for R-H. On the other hand, in regime (2), we found a negative R-H, which approaches zero for large B. The bend resistance is highly asymmetric in regime (2) and the resistance increases with increasing magnetic field B in one direction while it reduces to zero in the other direction. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4704667] |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
| Language |
|
Wos |
000303128500064 |
Publication Date |
2012-04-20 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0003-6951; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.411 |
Times cited |
20 |
Open Access |
|
| Notes |
; This work was supported by IMEC, the Flemish Science Foundation (FWO-Vl), the Belgian Science Policy (IAP), and the ESF-EuroGRAPHENE project CONGRAN. ; |
Approved |
Most recent IF: 3.411; 2012 IF: 3.794 |
| Call Number |
UA @ lucian @ c:irua:99129 |
Serial |
3047 |
| Permanent link to this record |
| |
|
| |
| Author |
Wendelen, W.; Mueller, B.Y.; Autrique, D.; Rethfeld, B.; Bogaerts, A. |
| Title |
Space charge corrected electron emission from an aluminum surface under non-equilibrium conditions |
Type |
A1 Journal article |
| Year |
2012 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
| Volume |
111 |
Issue |
11 |
Pages |
113110 |
| Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| Abstract |
A theoretical study has been conducted of ultrashort pulsed laser induced electron emission from an aluminum surface. Electron emission fluxes retrieved from the commonly employed Fowler-DuBridge theory were compared to fluxes based on a laser-induced non-equilibrium electron distribution. As a result, the two-and three-photon photoelectron emission parameters for the Fowler-DuBridge theory have been approximated. We observe that at regimes where photoemission is important, laser-induced electron emission evolves in a more smooth manner than predicted by the Fowler-DuBridge theory. The importance of the actual electron distribution decreases at higher laser fluences, whereas the contribution of thermionic emission increases. Furthermore, the influence of a space charge effect on electron emission was evaluated by a one dimensional particle-in-cell model. Depending on the fluences, the space charge reduces the electron emission by several orders of magnitude. The influence of the electron emission flux profiles on the effective electron emission was found to be negligible. However, a non-equilibrium electron velocity distribution increases the effective electron emission significantly. Our results show that it is essential to consider the non-equilibrium electron distribution as well as the space charge effect for the description of laser-induced photoemission. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4729071] |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
| Language |
|
Wos |
000305401400043 |
Publication Date |
2012-06-14 |
| 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 |
30 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 2.068; 2012 IF: 2.210 |
| Call Number |
UA @ lucian @ c:irua:100300 |
Serial |
3057 |
| Permanent link to this record |
| |
|
| |
| Author |
Fei, G.; Xue-Chun, L.; Zhao, S.-X.; You-Nian, W. |
| Title |
Spatial variation behaviors of argon inductively coupled plasma during discharge mode transition |
Type |
A1 Journal article |
| Year |
2012 |
Publication |
Chinese physics B |
Abbreviated Journal |
Chinese Phys B |
| Volume |
21 |
Issue |
7 |
Pages |
075203 |
| Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| Abstract |
A Langmuir probe and an ICCD are employed to study the discharge mode transition in Ar inductively coupled plasma. Electron density and plasma emission intensity are measured during the E (capacitive discharge) to H (inductive discharge) mode transitions at different pressures. It is found that plasma exists with a low electron density and a weak emission intensity in the E mode, while it has a high electron density and a strong emission intensity in the H mode. Meanwhile, the plasma emission intensity spatial (2D image) profile is symmetrical in the H mode, but the 2D image is an asymmetric profile in the E mode. Moreover, the electron density and emission intensity jump up discontinuously at high pressure, but increase almost continuously at the E to H mode transition under low pressure. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
IOP publishing |
Place of Publication |
Bristol |
Editor |
|
| Language |
|
Wos |
000306558300058 |
Publication Date |
2012-07-19 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1674-1056; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
1.223 |
Times cited |
11 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 1.223; 2012 IF: 1.148 |
| Call Number |
UA @ lucian @ c:irua:100843 |
Serial |
3065 |
| Permanent link to this record |
| |
|
| |
| Author |
Berdiyorov, G.R.; Milošević, M.V.; Peeters, F.M. |
| Title |
Spatially dependent sensitivity of superconducting meanders as single-photon detectors |
Type |
A1 Journal article |
| Year |
2012 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
| Volume |
100 |
Issue |
26 |
Pages |
262603 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
The photo-response of a thin current-carrying superconducting stripe with a 90 degrees turn is studied within the time-dependent Ginzburg-Landau theory. We show that the photon acting near the inner corner (where the current density is maximal due to the current crowding [J. R. Clem and K. K. Berggren, Phys. Rev. B 84, 174510 (2011)]) triggers the nucleation of superconducting vortices at currents much smaller than the expected critical one, but does not bring the system to a higher resistive state and thus remains undetected. The transition to the resistive state occurs only when the photon hits the stripe away from the corner due to there uniform current distribution across the sample, and dissipation is due to the nucleation of a kinematic vortex-antivortex pair near the photon incidence. We propose strategies to account for this problem in the measurements. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4731627] |
| Address |
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| Corporate Author |
|
Thesis |
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| Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
| Language |
|
Wos |
000305831500057 |
Publication Date |
2012-06-28 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0003-6951; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.411 |
Times cited |
27 |
Open Access |
|
| Notes |
; This work was supported by the Flemish Science Foundation (FWO-VI). G. R. B. acknowledges individual support from FWO-VI. ; |
Approved |
Most recent IF: 3.411; 2012 IF: 3.794 |
| Call Number |
UA @ lucian @ c:irua:100336 |
Serial |
3066 |
| Permanent link to this record |
| |
|
| |
| Author |
Gotter, R.; Fratesi, G.; Bartynski, R.A.; da Pieve, F.; Offi, F.; Ruocco, A.; Ugenti, S.; Trioni, M.I.; Brivio, G.P.; Stefani, G. |
| Title |
Spin-dependent on-site electron correlations and localization in itinerant f erromagnets |
Type |
A1 Journal article |
| Year |
2012 |
Publication |
Physical review letters |
Abbreviated Journal |
Phys Rev Lett |
| Volume |
109 |
Issue |
12 |
Pages |
126401 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Spin selectivity in angle-resolved Auger photoelectron coincidence spectroscopy (AR-APECS) is used to probe electron correlation in ferromagnetic thin films. In particular, exploiting the AR-APECS capability to discriminate Auger electron emission events characterized by valence hole pairs created either in the high or in the low total spin state, a strong correlation effect in the Fe M2,3VV Auger line shape (measured in coincidence with the Fe 3p photoelectrons) of Fe/Cu(001) thin films is detected and ascribed to interactions within the majority spin subband. Such an assignment follows from a close comparison of the experimental AR-APECS line shapes with the predictions of a model based on spin polarized density functional theory and the Cini-Sawatzky approach. |
| Address |
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| Corporate Author |
|
Thesis |
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| Publisher |
|
Place of Publication |
New York, N.Y. |
Editor |
|
| Language |
|
Wos |
000308877000002 |
Publication Date |
2012-09-21 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0031-9007;1079-7114; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
8.462 |
Times cited |
9 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 8.462; 2012 IF: 7.943 |
| Call Number |
UA @ lucian @ c:irua:101841 |
Serial |
3084 |
| Permanent link to this record |
| |
|
| |
| Author |
Szumniak, P.; Bednarek, S.; Partoens, B.; Peeters, F.M. |
| Title |
Spin-orbit-mediated manipulation of heavy-hole spin qubits in gated semiconductor nanodevices |
Type |
A1 Journal article |
| Year |
2012 |
Publication |
Physical review letters |
Abbreviated Journal |
Phys Rev Lett |
| Volume |
109 |
Issue |
10 |
Pages |
107201 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
A novel spintronic nanodevice is proposed that is able to manipulate the single heavy-hole spin state in a coherent manner. It can act as a single quantum logic gate. The heavy-hole spin transformations are realized by transporting the hole around closed loops defined by metal gates deposited on top of the nanodevice. The device exploits Dresselhaus spin-orbit interaction, which translates the spatial motion of the hole into a rotation of the spin. The proposed quantum gate operates on subnanosecond time scales and requires only the application of a weak static voltage which allows for addressing heavy-hole spin qubits individually. Our results are supported by quantum mechanical time-dependent calculations within the four-band Luttinger-Kohn model. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
New York, N.Y. |
Editor |
|
| Language |
|
Wos |
000308295700015 |
Publication Date |
2012-09-05 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0031-9007;1079-7114; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
8.462 |
Times cited |
41 |
Open Access |
|
| Notes |
; This work was supported by the Grant No. NN202 128337 from the Ministry of Science and Higher Education, as well as by the “Krakow Interdisciplinary PhD-Project in Nanoscience and Advances Nanostructures” operated within the Foundation for Polish Science MPD Programme and cofinanced by European Regional Development Fund, the Belgian Science Policy (IAP), and the Flemish Science Foundation (FWO-V1). ; |
Approved |
Most recent IF: 8.462; 2012 IF: 7.943 |
| Call Number |
UA @ lucian @ c:irua:101849 |
Serial |
3094 |
| 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 |
Fang, C.M.; van Huis, M.A.; Thijsse, B.J.; Zandbergen, H.W. |
| Title |
Stability and crystal structures of iron carbides : a comparison between the semi-empirical modified embedded atom method and quantum-mechanical DFT calculations |
Type |
A1 Journal article |
| Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| Volume |
85 |
Issue |
5 |
Pages |
054116-054116,7 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
Iron carbides play a crucial role in steel manufacturing and processing and to a large extent determine the physical properties of steel products. The modified embedded atom method (MEAM) in combination with Lee's Fe-C potential is a good candidate for molecular dynamics simulations on larger Fe-C systems. Here, we investigate the stability and crystal structures of pure iron and binary iron carbides using MEAM and compare them with the experimental data and quantum-mechanical density functional theory calculations. The analysis shows that the Fe-C potential gives reasonable results for the relative stability of iron and iron carbides. The performance of MEAM for the prediction of the potential energy and the calculated lattice parameters at elevated temperature for pure iron phases and cementite are investigated as well. The conclusion is that Lee's MEAM Fe-C potential provides a promising basis for further molecular dynamics simulations of Fe-C alloys and steels at lower temperatures (up to 800 K). |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000300931900004 |
Publication Date |
2012-02-29 |
| 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 |
18 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
| Call Number |
UA @ lucian @ c:irua:97201 |
Serial |
3117 |
| Permanent link to this record |
| |
|
| |
| Author |
Fang, C.M.; van Huis, M.A.; Zandbergen, H.W. |
| Title |
Stability and structures of the CFCC-TmC phases : a first-principles study |
Type |
A1 Journal article |
| Year |
2012 |
Publication |
Computational materials science |
Abbreviated Journal |
Comp Mater Sci |
| Volume |
51 |
Issue |
1 |
Pages |
146-150 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
The η-M6C, γ-M23C6, and π-M11C2 phases (M = Cr, Mn and Fe) have complex cubic lattices with lattice parameters of approximately 1.0 nm. They belong to the CFCC-TmC family (complex face-centered cubic transition metal carbides), display a rich variety of crystal structures, and play in important role in iron alloys and steels. Here we show that first-principles calculations predict high stability for the γ-M23C6 and η-M6C phases, and instability for the π-M11C2 phases, taking into account various compositional and structural possibilities. The calculations also show a wide variety in magnetic properties. The Cr-containing phases were found to be non-magnetic and the Fe-phases to be ferromagnetic, while the Mn-containing phases were found to be either ferrimagnetic or non-magnetic. Details of the local atomic structures, and the formation and stability of these precipitates in alloys are discussed. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Wos |
000296214300020 |
Publication Date |
2011-08-29 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0927-0256; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
2.292 |
Times cited |
18 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 2.292; 2012 IF: 1.878 |
| Call Number |
UA @ lucian @ c:irua:93277 |
Serial |
3119 |
| Permanent link to this record |
| |
|
| |
| Author |
Pina, J.C.; de Souza Silva, C.C.; Milošević, M.V. |
| Title |
Stability of fractional vortex states in a two-band mesoscopic superconductor |
Type |
A1 Journal article |
| Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| Volume |
86 |
Issue |
2 |
Pages |
024512 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
We investigate the stability of noncomposite fractional vortex states in a mesoscopic two-band superconductor within the two-component Ginzburg-Landau model. Our analysis explicitly takes into account the relationship between the model parameters and microscopic material parameters, such as partial density of states, Fermi velocities and elements of the electron-phonon coupling matrix. We have found that states with different phase winding number in each band (L-1 not equal L-2) and fractional flux can exist in many different configurations, including rather unconventional ones where the dominating band carries larger winding number and states where vertical bar L-1 – L-2 vertical bar > 1. We present a detailed analysis of the stability of the observed vortex structures with respect to changing the microscopic parameters, showing that, in the weak coupling case, fractional vortex states can be assessed in essentially the whole range of temperatures and applied magnetic fields in which both bands are active. Finally, we propose an efficient way of increasing the range of parameters for which these fractional vortex states can be stabilized. In particular, our proposal allows for observation of fractional vortex structures in materials with stronger coupling, where those states are forbidden at a homogeneous field. This is accomplished with the help of the stray fields of a suitably prepared magnetic dot placed nearby the superconducting disk. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
Lancaster, Pa |
Editor |
|
| Language |
|
Wos |
000306309600006 |
Publication Date |
2012-07-14 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.836 |
Times cited |
38 |
Open Access |
|
| Notes |
; We thank Eric B. Claude, Miguel A. Zorro, and Rogerio M. da Silva for assistance in the development of the numerical code used in our simulations. This work was supported by the Brazilian science agencies CNPq and FACEPE, by the FACEPE/CNPq-PRONEX program, under Grant No. APQ-0589-1.05/08, and by CNPq-FWO Brazil-Flanders co-operation program. M.V.M. acknowledges support from the CAPES-PVE program. ; |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
| Call Number |
UA @ lucian @ c:irua:100766 |
Serial |
3126 |
| Permanent link to this record |
| |
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| |
| Author |
Govaerts, K.; Sluiter, M.H.F.; Partoens, B.; Lamoen, D. |
| Title |
Stability of Sb-Te layered structures : first-principles study |
Type |
A1 Journal article |
| Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| Volume |
85 |
Issue |
14 |
Pages |
144114-144114,8 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) |
| Abstract |
Using an effective one-dimensional cluster expansion in combination with first-principles electronic structure calculations we have studied the energetics and electronic properties of Sb-Te layered systems. For a Te concentration between 0 and 60 at. % an almost continuous series of metastable structures is obtained consisting of consecutive Sb bilayers next to consecutive Sb2Te3 units, with the general formula (Sb-2)(n)(Sb2Te3)(m) (n, m = 1,2, ... ). Between 60 and 100 at.% no stable structures are found. We account explicitly for the weak van derWaals bonding between Sb bilayers and Sb2Te3 units by using a recently developed functional, which strongly improves the interlayer bonding distances. At T = 0 K, no evidence is found for the existence of two separate single-phase regions delta and gamma and a two-phase region delta + gamma. Metastable compounds with a Te concentration between 0 and 40 at. % are semimetallic, whereas compounds with a Te concentration between 50 and 60 at. % are semiconducting. Compounds with an odd number of Sb layers are metallic and have a much higher formation energy than those with an even number of consecutive Sb layers, thereby favoring the formation of Sb bilayers. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000303115400004 |
Publication Date |
2012-04-23 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.836 |
Times cited |
14 |
Open Access |
|
| Notes |
Iwt; Fwo |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
| Call Number |
UA @ lucian @ c:irua:98255 |
Serial |
3129 |
| Permanent link to this record |
| |
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| |
| Author |
Van Aert, S. |
| Title |
Statistical parameter estimation theory : a tool for quantitative electron microscopy |
Type |
H1 Book chapter |
| Year |
2012 |
Publication |
|
Abbreviated Journal |
|
| Volume |
|
Issue |
|
Pages |
281-309 |
| Keywords |
H1 Book chapter; Electron microscopy for materials research (EMAT) |
| Abstract |
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| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
Wiley-VCH |
Place of Publication |
Weinheim |
Editor |
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| Language |
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Wos |
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Publication Date |
0000-00-00 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
|
Edition |
|
| ISSN |
|
ISBN |
978-3-527-31706-6 |
Additional Links |
UA library record |
| Impact Factor |
|
Times cited |
|
Open Access |
|
| Notes |
|
Approved |
Most recent IF: NA |
| Call Number |
UA @ lucian @ c:irua:96693 |
Serial |
3159 |
| Permanent link to this record |
| |
|
| |
| Author |
Grzelczak, M.; Sánchez-Iglesias, A.; Heidari Mezerji, H.; Bals, S.; Pérez-Juste, J.; Liz-Marzán, L.M. |
| Title |
Steric hindrance induces crosslike self-assembly of gold nanodumbbells |
Type |
A1 Journal article |
| Year |
2012 |
Publication |
Nano letters |
Abbreviated Journal |
Nano Lett |
| Volume |
12 |
Issue |
8 |
Pages |
4380-4384 |
| Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
| Abstract |
In the formation of colloidal molecules, directional interactions are crucial for controlling the spatial distribution of the building blocks. Anisotropic nanoparticles facilitate directional clustering via steric constraints imposed by each specific shape, thereby restricting assembly along certain directions. We show in this Letter that the combination of patchiness (attraction) and shape (steric hindrance) allows assembling gold nanodumbbell building blocks into crosslike dimers with well-controlled interparticle distance and relative orientation. Steric hindrance between interacting dumbbell-like particles opens up a new synthetic approach toward low-symmetry plasmonic clusters, which may significantly contribute to understand complex plasmonic phenomena. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
Washington |
Editor |
|
| Language |
|
Wos |
000307211000081 |
Publication Date |
2012-07-05 |
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1530-6984;1530-6992; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
12.712 |
Times cited |
85 |
Open Access |
|
| Notes |
Nanodirect 213948-2; 262348 Esmi |
Approved |
Most recent IF: 12.712; 2012 IF: 13.025 |
| Call Number |
UA @ lucian @ c:irua:101900 |
Serial |
3161 |
| Permanent link to this record |
| |
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| |
| Author |
Neek-Amal, M.; Peeters, F.M. |
| Title |
Strain-engineered graphene through a nanostructured substrate : 1 : deformations |
Type |
A1 Journal article |
| Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| Volume |
85 |
Issue |
19 |
Pages |
195445-195445,11 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
Using atomistic simulations we investigate the morphological properties of graphene deposited on top of a nanostructured substrate. Sinusoidally corrugated surfaces, steps, elongated trenches, one-dimensional and cubic barriers, spherical bubbles, Gaussian bumps, and Gaussian depressions are considered as support structures for graphene. The graphene-substrate interaction is governed by van der Waals forces and the profile of the graphene layer is determined by minimizing the energy using molecular dynamics simulations. Based on the obtained optimum configurations, we found that (i) for graphene placed over sinusoidally corrugated substrates with corrugation wavelengths longer than 2 nm, the graphene sheet follows the substrate pattern while for supported graphene it is always suspended across the peaks of the substrate, (ii) the conformation of graphene to the substrate topography is enhanced when increasing the energy parameter in the van der Waals model, (iii) the adhesion of graphene into the trenches depends on the width of the trench and on the graphene's orientation, i. e., in contrast to a small-width (3 nm) nanoribbon with armchair edges, the one with zigzag edges follows the substrate profile, (iv) atomic-scale graphene follows a Gaussian bump substrate but not the substrate with a Gaussian depression, and (v) the adhesion energy due to van der Waals interaction varies in the range [0.1-0.4] J/m(2). |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000304394800012 |
Publication Date |
2012-05-23 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.836 |
Times cited |
62 |
Open Access |
|
| Notes |
; We thank L. Covaci and S. Costamagna for valuable comments. We acknowledge M. Zarenia, M. R. Masir and D. Nasr for fruitful discussions. This work was supported by the Flemish Science Foundation (FWO-Vl) and ESF EUROCORE program EuroGRAPHENE: CONGRAN. ; |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
| Call Number |
UA @ lucian @ c:irua:98942 |
Serial |
3166 |
| Permanent link to this record |
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| |
| Author |
Neek-Amal, M.; Peeters, F.M. |
| Title |
Strain-engineered graphene through a nanostructured substrate : 2 : pseudomagnetic fields |
Type |
A1 Journal article |
| Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| Volume |
85 |
Issue |
19 |
Pages |
195446-195446,6 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
The strain-induced pseudomagnetic field in supported graphene deposited on top of a nanostructured substrate is investigated by using atomistic simulations. A step, an elongated trench, a one-dimensional barrier, a spherical bubble, a Gaussian bump, and a Gaussian depression are considered as support structures for graphene. From the obtained optimum configurations we found very strong induced pseudomagnetic fields which can reach up to similar to 1000 T due to the strain-induced deformations in the supported graphene. Different magnetic confinements with controllable geometries are found by tuning the pattern of the substrate. The resulting induced magnetic fields for graphene on top of a step, barrier, and trench are calculated. In contrast to the step and trench the middle part of graphene on top of a barrier has zero pseudomagnetic field. This study provides a theoretical background for designing magnetic structures in graphene by nanostructuring substrates. We found that altering the radial symmetry of the deformation changes the sixfold symmetry of the induced pseudomagnetic field. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000304394800013 |
Publication Date |
2012-05-23 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.836 |
Times cited |
31 |
Open Access |
|
| Notes |
; This work was supported by the Flemish Science Foundation (FWO-Vl) and the ESF EUROCORE program EuroGRAPHENE: CONGRAN. ; |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
| Call Number |
UA @ lucian @ c:irua:98943 |
Serial |
3167 |
| Permanent link to this record |
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| |
| Author |
Verberck, B.; Partoens, B.; Peeters, F.M.; Trauzettel, B. |
| Title |
Strain-induced band gaps in bilayer graphene |
Type |
A1 Journal article |
| Year |
2012 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
| Volume |
85 |
Issue |
12 |
Pages |
125403-125403,10 |
| Keywords |
A1 Journal article; Condensed Matter Theory (CMT) |
| Abstract |
We present a tight-binding investigation of strained bilayer graphene within linear elasticity theory, focusing on the different environments experienced by the A and B carbon atoms of the different sublattices. We find that the inequivalence of the A and B atoms is enhanced by the application of perpendicular strain epsilon(zz), which provides a physical mechanism for opening a band gap, most effectively obtained when pulling the two graphene layers apart. In addition, perpendicular strain introduces electron-hole asymmetry and can result in linear electronic dispersion near the K point. Our findings suggest experimental means for strain-engineered band gaps in bilayer graphene. |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000301113200005 |
Publication Date |
2012-03-06 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
1098-0121;1550-235X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
3.836 |
Times cited |
53 |
Open Access |
|
| Notes |
; The authors would like to acknowledge O. Leenaerts, E. Mariani, K. H. Michel, and J. Schelter for useful discussions. B. V. was financially supported by the Flemish Science Foundation (FWO-Vl). This work was financially supported by the ESF program EuroGraphene under projects CONGRAN and ENTS as well as by the DFG. ; |
Approved |
Most recent IF: 3.836; 2012 IF: 3.767 |
| Call Number |
UA @ lucian @ c:irua:97181 |
Serial |
3168 |
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| Author |
Scalise, E.; Houssa, M.; Pourtois, G.; Afanas'ev, V.; Stesmans, A. |
| Title |
Strain-induced semiconductor to metal transition in the two-dimensional honeycomb structure of MoS2 |
Type |
A1 Journal article |
| Year |
2012 |
Publication |
Nano Research |
Abbreviated Journal |
Nano Res |
| Volume |
5 |
Issue |
1 |
Pages |
43-48 |
| Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
| Abstract |
The electronic properties of two-dimensional honeycomb structures of molybdenum disulfide (MoS(2)) subjected to biaxial strain have been investigated using first-principles calculations based on density functional theory. On applying compressive or tensile bi-axial strain on bi-layer and mono-layer MoS(2), the electronic properties are predicted to change from semiconducting to metallic. These changes present very interesting possibilities for engineering the electronic properties of two-dimensional structures of MoS(2). |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000299085200006 |
Publication Date |
2011-11-10 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1998-0124;1998-0000; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| Impact Factor |
7.354 |
Times cited |
407 |
Open Access |
|
| Notes |
|
Approved |
Most recent IF: 7.354; 2012 IF: 7.392 |
| Call Number |
UA @ lucian @ c:irua:96262 |
Serial |
3169 |
| Permanent link to this record |
