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Author  |
Bellizotti Souza, J.C.; Vizarim, N.P.; Reichhardt, C.J.O.; Reichhardt, C.; Venegas, P.A. | ||||
| Title | Spontaneous skyrmion conformal lattice and transverse motion during dc and ac compression | Type | A1 Journal article | ||
| Year | 2023 | Publication | New journal of physics | Abbreviated Journal | |
| Volume | 25 | Issue | 5 | Pages | 053020-15 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | We use atomistic-based simulations to investigate the behavior of ferromagnetic skyrmions being continuously compressed against a rigid wall under dc and ac drives. The compressed skyrmions can be annihilated close to the wall and form a conformal crystal with both a size and a density gradient, making it distinct from conformal crystals observed previously for superconducting vortices and colloidal particles. For both dc and ac driving, the skyrmions can move transverse to the compression direction due to a combination of density and size gradients. Forces in the compression direction are converted by the Magnus force into transverse motion. Under ac driving, the amount of skyrmion annihilation is reduced and we find a skyrmion Magnus ratchet pump. We also observe shear banding in which skyrmions near the wall move up to twice as fast as skyrmions further from the wall. When we vary the magnitude of the applied drive, we find a critical current above which the skyrmions are completely annihilated during a time scale that depends on the magnitude of the drive. By varying the magnetic parameters, we find that the transverse motion is strongly dependent on the skyrmion size. Smaller skyrmions are more rigid, which interferes with the size gradient and destroys the transverse motion. We also confirm the role of the size gradient by comparing our atomistic simulations with a particle-based model, where we find that the transverse motion is only transient. Our results are relevant for applications where skyrmions encounter repulsive magnetic walls, domain walls, or interfaces. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000994003200001 | Publication Date | 2023-05-11 | |
| 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 | Open Access | OpenAccess | |
| Notes | Approved | Most recent IF: 3.3; 2023 IF: 3.786 | |||
| Call Number | UA @ admin @ c:irua:197365 | Serial | 8934 | ||
| Permanent link to this record | |||||
| Author |
Belikov, K.N.; Mikhailova, L.I.; Spolnik, Z.M.; Van Grieken, R. | ||||
| Title | EDXRF determination of impurities in potassium dihydrogenphosphate single crystals and raw materials | Type | A1 Journal article | ||
| Year | 2006 | Publication | X-ray spectrometry | Abbreviated Journal | |
| Volume | 35 | Issue | 2 | Pages | 112-115 |
| Keywords | A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) | ||||
| Abstract | |||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000236405500005 | Publication Date | 2005-10-14 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0049-8246 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | Times cited | Open Access | |||
| Notes | Approved | no | |||
| Call Number | UA @ admin @ c:irua:56727 | Serial | 7835 | ||
| Permanent link to this record | |||||
| Author |
Belik, A.A.; Morozov, V.A.; Deyneko, D.V.; Savon, A.E.; Baryshnikova, O.V.; Zhukovskaya, E.S.; Dorbakov, N.G.; Katsuya, Y.; Tanaka, M.; Stefanovich, S.Y.; Hadermann, J.; Lazoryak, B.I. | ||||
| Title | Antiferroelectric properties and site occupations ofR3+ cations in Ca8MgR(PO4)7 luminescent host materials | Type | A1 Journal article | ||
| Year | 2017 | Publication | Journal of alloys and compounds | Abbreviated Journal | |
| Volume | 699 | Issue | Pages | 928-937 | |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Ca8MgR(PO4)(7) = La, Pr, Nd, Sm-Lu, and Y) phosphates with a beta-Ca-3(PO4)(2) related structure were prepared by a standard solid-state method in air. Second-harmonic generation, differential scanning calorimetry, and dielectric measurements led to the conclusion that all Ca8MgR(PO4)(7) are centrosymmetric and go to another centrosymmetric phase in the course of a first-order antiferroelectric phase transition well above room temperature (RT). High-temperature electron diffraction showed that the symmetry changes from R (3) over barc to R (3) over barm during the phase transition. Structures of Ca8MgR(PO4)(7) at RT were refined by the Rietveld method in centrosymmetric space group R (3) over barc. Mg2+ cations occupy the M5 site; the occupancy of the M1 site by R3+ cations increases monotonically from 0.0389 for R = La to 0.1667 for R = Er-Lu, whereas the occupancy of the M3 site by R3+ cations decreases monotonically from 0.1278 for R = La to 0 for R = Er-Lu. In the case of R = Er-Lu, the M3 site is occupied only by Ca2+ cations. P1O(4) tetrahedra and cations at the M3 site are disordered in the R (3) over barc structure of Ca8MgEu(PO4)(7). Using synchrotron X-ray powder diffraction, we found that annealing conditions do not significantly affect the distribution of Ca2+ and Eu3+ cations between the structure positions of Ca8MgEu(PO4)(7). Luminescent properties of CasMgEu(PO4)(7) powder samples were investigated under near-ultraviolet (n-UV) light. Excitation spectra of CasMgEu(PO4)(7) show the strongest absorption at about 395 nm that matches with commercially available n-UV-emitting GaN-based LED chips. Emission spectra show an intense red emission due to the D-5(0) -> F-7(2) transition of Eu3+. (C) 2016 Elsevier B.V. All rights reserved. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000393727500129 | Publication Date | 2016-12-24 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0925-8388 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | Times cited | Open Access | |||
| Notes | Approved | no | |||
| Call Number | UA @ admin @ c:irua:152665 | Serial | 7464 | ||
| Permanent link to this record | |||||
| Author |
Belik, A.A.; Abakumov, A.M.; Tsirlin, A.A.; Hadermann, J.; Kim, J.; Van Tendeloo, G.; Takayama-Muromachi, E. | ||||
| Title | Article Structure and magnetic properties of BiFe0.75Mn0.25O3 perovskite prepared at ambient and high pressure | Type | A1 Journal article | ||
| Year | 2011 | Publication | Chemistry of materials | Abbreviated Journal | Chem Mater |
| Volume | 23 | Issue | 20 | Pages | 4505-4514 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Solid solutions of BiFe1xMnxO3 (0.0 ≤ x ≤ 0.4) were prepared at ambient pressure and at 6 GPa. The ambient-pressure (AP) phases crystallize in space group R3c similarly to BiFeO3. The high-pressure (HP) phases crystallize in space group R3c for x = 0.05 and in space group Pnma for 0.15 ≤ x ≤ 0.4. The structure of HP-BiFe0.75Mn0.25O3 was investigated using synchrotron X-ray powder diffraction, electron diffraction, and transmission electron microscopy. HP-BiFe0.75Mn0.25O3 has a PbZrO3-related √2ap × 4ap × 2√2ap (ap is the parameter of the cubic perovskite subcell) superstructure with a = 5.60125(9) Å, b = 15.6610(2) Å, and c = 11.2515(2) Å similar to that of Bi0.82La0.18FeO3. A remarkable feature of this structure is the unconventional octahedral tilt system, with the primary ab0a tilt superimposed on pairwise clockwise and counterclockwise rotations around the b-axis according to the oioi sequence (o stands for out-of-phase tilt, and i stands for in-phase tilt). The (FeMn)O6 octahedra are distorted, with one longer metaloxygen bond (2.222.23 Å) that can be attributed to a compensation for covalent BiO bonding. Such bonding results in the localization of the lone electron pair on Bi3+ cations, as confirmed by electron localization function analysis. The relationship between HP-BiFe0.75Mn0.25O3 and antiferroelectric structures of PbZrO3 and NaNbO3 is discussed. On heating in air, HP-BiFe0.75Mn0.25O3 irreversibly transforms to AP-BiFe0.75Mn0.25O3 starting from about 600 K. Both AP and HP phases undergo an antiferromagnetic ordering at TN ≈ 485 and 520 K, respectively, and develop a weak net magnetic moment at low temperatures. Additionally, ceramic samples of AP-BiFe0.75Mn0.25O3 show a peculiar phenomenon of magnetization reversal. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Washington, D.C. | Editor | ||
| Language | Wos | 000295897400015 | Publication Date | 2011-09-29 | |
| 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 | 57 | Open Access | |
| Notes | Approved | Most recent IF: 9.466; 2011 IF: 7.286 | |||
| Call Number | UA @ lucian @ c:irua:93581 | Serial | 151 | ||
| Permanent link to this record | |||||
| Author |
Belik, A.; Izumi, F.; Ikeda, T.; Morozov, V.A.; Dilanian, R.; Torii, S.; Kopnin, E.; Lebedev, O.I.; Van Tendeloo, G.; Lazoryak, B.I. | ||||
| Title | Positional and orientational disorder in a solid solution of Sr9-xNi1.5-x(PO4)7 (x=0.3) | Type | A1 Journal article | ||
| Year | 2002 | Publication | Chemistry and materials | Abbreviated Journal | Chem Mater |
| Volume | 14 | Issue | Pages | 4464-4472 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | |||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000178782900069 | Publication Date | 2002-10-21 | |
| 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 | 28 | Open Access | |
| Notes | Approved | Most recent IF: 9.466; 2002 IF: 3.967 | |||
| Call Number | UA @ lucian @ c:irua:54768 | Serial | 2676 | ||
| Permanent link to this record | |||||
| Author |
Bekshaev, A.; Van Grieken, R. | ||||
| Title | Interference technique in grazing-emission electron probe microanalysis of submicrometer particles | Type | A1 Journal article | ||
| Year | 2001 | Publication | Spectrochimica acta: part B : atomic spectroscopy | Abbreviated Journal | |
| Volume | 56 | Issue | Pages | 503-515 | |
| Keywords | A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) | ||||
| Abstract | |||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000169972200003 | Publication Date | 2002-07-25 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0584-8547; 1873-3565 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | Times cited | Open Access | |||
| Notes | Approved | no | |||
| Call Number | UA @ admin @ c:irua:36083 | Serial | 8115 | ||
| Permanent link to this record | |||||
| Author |
Bekshaev, A.; Van Grieken, R. | ||||
| Title | Substrates with a periodic surface structure in grazing-exit X-ray microanalysis | Type | A1 Journal article | ||
| Year | 2002 | Publication | Spectrochimica acta: part B : atomic spectroscopy | Abbreviated Journal | |
| Volume | 57 | Issue | Pages | 865-882 | |
| Keywords | A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) | ||||
| Abstract | |||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000177033500005 | Publication Date | 2003-02-28 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0584-8547; 1873-3565 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | Times cited | Open Access | |||
| Notes | Approved | no | |||
| Call Number | UA @ admin @ c:irua:39516 | Serial | 8615 | ||
| Permanent link to this record | |||||
| Author |
Bekshaev, A.; de Hoog, J.; Van Grieken, R. | ||||
| Title | Grazing-emission electron probe microanalysis of particles near the substrate edge | Type | A1 Journal article | ||
| Year | 2001 | Publication | Spectrochimica acta: part B : atomic spectroscopy | Abbreviated Journal | |
| Volume | 56 | Issue | Pages | 2385-2395 | |
| Keywords | A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) | ||||
| Abstract | |||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000173118900005 | Publication Date | 2002-07-25 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0584-8547; 1873-3565 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | Times cited | Open Access | |||
| Notes | Approved | no | |||
| Call Number | UA @ admin @ c:irua:36384 | Serial | 8007 | ||
| Permanent link to this record | |||||
| Author |
Bekeschus, S.; Lin, A.; Fridman, A.; Wende, K.; Weltmann, K.-D.; Miller, V. | ||||
| Title | A comparison of floating-electrode DBD and kINPen jet : plasma parameters to achieve similar growth reduction in colon cancer cells under standardized conditions | Type | A1 Journal article | ||
| Year | 2018 | Publication | Plasma chemistry and plasma processing | Abbreviated Journal | Plasma Chem Plasma P |
| Volume | 38 | Issue | 1 | Pages | 1-12 |
| Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
| Abstract | A comparative study of two plasma sources (floating-electrode dielectric barrier discharge, DBD, Drexel University; atmospheric pressure argon plasma jet, kINPen, INP Greifswald) on cancer cell toxicity was performed. Cell culture protocols, cytotoxicity assays, and procedures for assessment of hydrogen peroxide (H2O2) were standardized between both labs. The inhibitory concentration 50 (IC50) and its corresponding H2O2 deposition was determined for both devices. For the DBD, IC50 and H2O2 generation were largely dependent on the total energy input but not pulsing frequency, treatment time, or total number of cells. DBD cytotoxicity could not be replicated by addition of H2O2 alone and was inhibited by larger amounts of liquid present during the treatment. Jet plasma toxicity depended on peroxide generation as well as total cell number and amount of liquid. Thus, the amount of liquid present during plasma treatment in vitro is key in attenuating short-lived species or other physical effects from plasmas. These in vitro results suggest a role of liquids in or on tissues during plasma treatment in a clinical setting. Additionally, we provide a platform for correlation between different plasma sources for a predefined cellular response. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | New York | Editor | ||
| Language | Wos | 000419479000001 | Publication Date | 2017-09-06 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0272-4324 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.355 | Times cited | 12 | Open Access | OpenAccess |
| Notes | Approved | Most recent IF: 2.355 | |||
| Call Number | UA @ lucian @ c:irua:155653 | Serial | 5084 | ||
| Permanent link to this record | |||||
| Author |
Bekeschus, S.; Freund, E.; Spadola, C.; Privat-Maldonado, A.; Hackbarth, C.; Bogaerts, A.; Schmidt, A.; Wende, K.; Weltmann, K.-D.; von Woedtke, T.; Heidecke, C.-D.; Partecke, L.-I.; Käding, A. | ||||
| Title | Risk Assessment of kINPen Plasma Treatment of Four Human Pancreatic Cancer Cell Lines with Respect to Metastasis | Type | A1 Journal article | ||
| Year | 2019 | Publication | Cancers | Abbreviated Journal | Cancers |
| Volume | 11 | Issue | 9 | Pages | 1237 |
| Keywords | A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) | ||||
| Abstract | Cold physical plasma has limited tumor growth in many preclinical models and is, therefore, suggested as a putative therapeutic option against cancer. Yet, studies investigating the cells’ metastatic behavior following plasma treatment are scarce, although being of prime importance to evaluate the safety of this technology. Therefore, we investigated four human pancreatic cancer cell lines for their metastatic behavior in vitro and in chicken embryos (in ovo). Pancreatic cancer was chosen as it is particularly metastatic to the peritoneum and systemically, which is most predictive for outcome. In vitro, treatment with the kINPen plasma jet reduced pancreatic cancer cell activity and viability, along with unchanged or decreased motility. Additionally, the expression of adhesion markers relevant for metastasis was down-regulated, except for increased CD49d. Analysis of 3D tumor spheroid outgrowth showed a lack of plasma-spurred metastatic behavior. Finally, analysis of tumor tissue grown on chicken embryos validated the absence of an increase of metabolically active cells physically or chemically detached with plasma treatment. We conclude that plasma treatment is a safe and promising therapeutic option and that it does not promote metastatic behavior in pancreatic cancer cells in vitro and in ovo. | ||||
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| Language | Wos | 000489719000022 | Publication Date | 2019-08-23 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2072-6694 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | Times cited | 4 | Open Access | ||
| Notes | The authors acknowledge that this work was supported by grants funded by the German Federal Ministry of Education and Research (BMBF), grant number 03Z22DN11. We want to thank the Research Foundation – Flanders (FWO) for providing funding to APM under the “long stay abroad” scheme (grant code V415618N). APM and AB acknowledge financial support from the Methusalem project. Technical support by Felix Niessner and Antje Janetzko is gratefully acknowledged. | Approved | Most recent IF: NA | ||
| Call Number | PLASMANT @ plasmant @c:irua:162106 | Serial | 5357 | ||
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| Author |
Bekermann, D.; Gasparotto, A.; Barreca, D.; Devi, A.; Fischer, R.A.; Kete, M.; Štangar, U.L.; Lebedev, O.I.; Maccato, C.; Tondello, E.; Van Tendeloo, G. | ||||
| Title | ZnO nanorod arrays by plasma-enhanced CVD for light-activated functional applications | Type | A1 Journal article | ||
| Year | 2010 | Publication | ChemPhysChem : a European journal of chemical physics and physical chemistry | Abbreviated Journal | Chemphyschem |
| Volume | 11 | Issue | 11 | Pages | 2337-2340 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Switch of the surface properties: Supported ZnO nanorod arrays with tailored roughness and aspect ratios are successfully synthesized by plasma-enhanced chemical vapor deposition. Such nanostructures exhibit significant superhydrophilic and photocatalytic properties tunable as a function of their morphological organization (see picture). This renders them promising building blocks for the fabrication of stimuli-responsive materials. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Weinheim | Editor | ||
| Language | Wos | 000281061500008 | Publication Date | 2010-06-16 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1439-4235;1439-7641; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.075 | Times cited | 38 | Open Access | |
| Notes | Esteem 026019 | Approved | Most recent IF: 3.075; 2010 IF: 3.340 | ||
| Call Number | UA @ lucian @ c:irua:84594 | Serial | 3935 | ||
| Permanent link to this record | |||||
| Author |
Bekermann, D.; Gasparotto, A.; Barreca, D.; Bovo, L.; Devi, A.; Fischer, R.A.; Lebedev, O.I.; Maccato, C.; Tondello, E.; Van Tendeloo, G. | ||||
| Title | Highly oriented ZnO nanorod arrays by a novel plasma chemical vapor deposition process | Type | A1 Journal article | ||
| Year | 2010 | Publication | Crystal growth & design | Abbreviated Journal | Cryst Growth Des |
| Volume | 10 | Issue | 4 | Pages | 2011-2018 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Strongly c-axis oriented ZnO nanorod arrays were grown on Si(100) by plasma enhanced-chemical vapor deposition (PE-CVD) starting from two volatile bis(ketoiminato) zinc(II) compounds Zn[(R′)NC(CH3)═C(H)C(CH3)═O]2, with R′ = -(CH2)xOCH3 (x = 2, 3). A systematic investigation of process parameters enabled us to obtain the selective formation of ZnO nanorods with tailored features, and provided an important insight into their growth mechanism. The morphology, structure, and composition of the synthesized ZnO nanosystems were thoroughly analyzed by field emission-scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDXS), glancing incidence X-ray diffraction (GIXRD), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). Photoluminescence (PL) measurements were carried out to gain information on the optical properties. Specifically, one-dimensional (1D) ZnO architectures could be grown on Si(100) substrates at temperatures as low as 200−300 °C and radio frequency (RF)-power values of 20 W, provided that a sufficiently high mass supply to the growth surface was maintained. To the best of our knowledge, the present work reports the mildest preparation conditions ever appeared in the literature for the PE-CVD of ZnO nanorods, a key result in view of potential large-scale technological applications. | ||||
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| Language | Wos | 000276234500080 | Publication Date | 2010-03-18 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1528-7483;1528-7505; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.055 | Times cited | 75 | Open Access | |
| Notes | Esteem 026019 | Approved | Most recent IF: 4.055; 2010 IF: 4.390 | ||
| Call Number | UA @ lucian @ c:irua:82311 | Serial | 1472 | ||
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| Author |
Bekaert, J.; Vercauteren, S.; Aperis, A.; Komendová, L.; Prozorov, R.; Partoens, B.; Milošević, M.V. | ||||
| Title | Anisotropic type-I superconductivity and anomalous superfluid density in OsB2 | Type | A1 Journal article | ||
| Year | 2016 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
| Volume | 94 | Issue | 94 | Pages | 144506 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | We present a microscopic study of superconductivity in OsB2 , and discuss the origin and characteristic length scales of the superconducting state. From first-principles we show that OsB2 is characterized by three different Fermi sheets, and we prove that this fermiology complies with recent quantum-oscillation experiments. Using the found microscopic properties, and experimental data from the literature, we employ Ginzburg-Landau relations to reveal that OsB2 is a distinctly type-I superconductor with a very low Ginzburg-Landau parameter κ—a rare property among compound materials. We show that the found coherence length and penetration depth corroborate the measured thermodynamic critical field. Moreover, our calculation of the superconducting gap structure using anisotropic Eliashberg theory and ab initio calculated electron-phonon interaction as input reveals a single but anisotropic gap. The calculated gap spectrum is shown to give an excellent account for the unconventional behavior of the superfluid density of OsB2 measured in experiments as a function of temperature. This reveals that gap anisotropy can explain such behavior, observed in several compounds, which was previously attributed solely to a two-gap nature of superconductivity. |
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| Language | Wos | 000385622500009 | Publication Date | 2016-10-12 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 19 | Open Access | |
| Notes | Fonds Wetenschappelijk Onderzoek; European Cooperation in Science and Technology, MP1201 ; Vetenskapsrådet; | Approved | Most recent IF: 3.836 | ||
| Call Number | CMT @ cmt @ c:irua:139020 | Serial | 4338 | ||
| Permanent link to this record | |||||
| Author |
Bekaert, J.; Sevik, C.; Milošević, M.V. | ||||
| Title | First-principles exploration of superconductivity in MXenes | Type | A1 Journal article | ||
| Year | 2020 | Publication | Nanoscale | Abbreviated Journal | Nanoscale |
| Volume | 12 | Issue | Pages | 17354-17361 | |
| Keywords | A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) | ||||
| Abstract | MXenes are an emerging class of two-dimensional materials, which in their thinnest limit consist of a monolayer of carbon or nitrogen (X) sandwiched between two transition metal (M) layers. We have systematically searched for superconductivity among MXenes for a range of transition metal elements, based on a full first-principles characterization in combination with the Eliashberg formalism. Thus, we identified six superconducting MXenes: three carbides (Mo2C, W2C and Sc2C) and three nitrides (Mo2N, W2N and Ta2N). The highest critical temperature of similar to 16 K is found in Mo2N, for which a successful synthesis method has been established [Urbankowskiet al.,Nanoscale, 2017,9, 17722-17730]. Moreover, W2N presents a novel case of competing superconducting and charge density wave phases. | ||||
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| Language | Wos | 000563481700017 | Publication Date | 2020-08-07 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2040-3364 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 6.7 | Times cited | 15 | Open Access | |
| Notes | ; This work is supported by The Scientific and Technological Research Council of Turkey (TUBITAK) under the contract number COST-118F187, the Air Force Office of Scientific Research under award number FA9550-19-1-7048, by Research Foundation-Flanders (FWO) and the University of Antwerp (BOF). The collaboration was fostered by COST action NANOCOHYBRI (CA16218). Computational resources were provided by the High Performance and Grid Computing Center (TRGrid e-Infrastructure) of TUBITAK ULAKBIM, the National Center for High Performance Computing (UHeM) of Istanbul Technical University, and by the VSC (Flemish Supercomputer Center), funded by the FWO and the Flemish Government – department EWI. J. B. acknowledges support of a postdoctoral fellowship of the FWO. ; | Approved | Most recent IF: 6.7; 2020 IF: 7.367 | ||
| Call Number | UA @ admin @ c:irua:171988 | Serial | 6521 | ||
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| Author |
Bekaert, J.; Sevik, C.; Milošević, M.V. | ||||
| Title | Enhancing superconductivity in MXenes through hydrogenation | Type | A1 Journal article | ||
| Year | 2022 | Publication | Nanoscale | Abbreviated Journal | Nanoscale |
| Volume | 14 | Issue | 27 | Pages | 9918-9924 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) | ||||
| Abstract | Two-dimensional transition metal carbides and nitrides (MXenes) are an emerging class of atomically-thin superconductors, whose characteristics are highly prone to tailoring by surface functionalization. Here we explore the use of hydrogen adatoms to enhance phonon-mediated superconductivity in MXenes, based on first-principles calculations combined with Eliashberg theory. We first demonstrate the stability of three different structural models of hydrogenated Mo- and W-based MXenes. Particularly high critical temperatures of over 30 K are obtained for hydrogenated Mo2N and W2N. Several mechanisms responsible for the enhanced electron-phonon coupling are uncovered, namely (i) hydrogen-induced changes in the phonon spectrum of the host MXene, (ii) emerging hydrogen-based phonon modes, and (iii) charge transfer from hydrogen to the MXene layer, boosting the density of states at the Fermi level. Finally, we demonstrate that hydrogen adatoms are moreover able to induce superconductivity in MXenes that are not superconducting in pristine form, such as Nb2C. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000820350600001 | Publication Date | 2022-06-27 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2040-3364; 2040-3372 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 6.7 | Times cited | 2 | Open Access | OpenAccess |
| Notes | Approved | Most recent IF: 6.7 | |||
| Call Number | UA @ admin @ c:irua:189580 | Serial | 7155 | ||
| Permanent link to this record | |||||
| Author |
Bekaert, J.; Saniz, R.; Partoens, B.; Lamoen, D. | ||||
| Title | First-principles study of carbon impurities in CuInSe2 and CuGaSe2, present in non-vacuum synthesis methods | Type | A1 Journal article | ||
| Year | 2015 | Publication | Journal of applied physics | Abbreviated Journal | J Appl Phys |
| Volume | 117 | Issue | 117 | Pages | 015104 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
| Abstract | A first-principles study of the structural and electronic properties of carbon impurities in CuInSe2 and CuGaSe2 is presented. Carbon is present in organic molecules in the precursor solutions used in non-vacuum growth methods for CuInSe2 and CuGaSe2 based photovoltaic cells. These growth methods make more efficient use of material, time, and energy than traditional vacuum methods. The formation energies of several carbon impurities are calculated using the hybrid HSE06 functional. C Cu acts as a shallow donor, CIn and interstitial C yield deep donor levels in CuInSe2, while in CuGaSe2 CGa and interstitial C act as deep amphoteric defects. So, these defects reduce the majority carrier (hole) concentration in p-type CuInSe2 and CuGaSe2 by compensating the acceptor levels. The deep defects are likely to act as recombination centers for the photogenerated charge carriers and are thus detrimental for the performance of the photovoltaic cells. On the other hand, the formation energies of the carbon impurities are high, even under C-rich growth conditions. Thus, few C impurities will form in CuInSe2 and CuGaSe2 in thermodynamic equilibrium. However, the deposition of the precursor solution in non-vacuum growth methods presents conditions far from thermodynamic equilibrium. In this case, our calculations show that C impurities formed in non-equilibrium tend to segregate from CuInSe2 and CuGaSe2 by approaching thermodynamic equilibrium, e.g., via thorough annealing. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | American Institute of Physics | Place of Publication | New York, N.Y. | Editor | |
| Language | Wos | 000347958600055 | Publication Date | 2015-01-07 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0021-8979;1089-7550; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.068 | Times cited | 6 | Open Access | |
| Notes | FWO G015013; Hercules | Approved | Most recent IF: 2.068; 2015 IF: 2.183 | ||
| Call Number | c:irua:122064 | Serial | 1215 | ||
| Permanent link to this record | |||||
| Author |
Bekaert, J.; Saniz, R.; Partoens, B.; Lamoen, D. | ||||
| Title | Native point defects in CuIn1-xGaxSe2 : hybrid density functional calculations predict the origin of p- and n-type conductivity | Type | A1 Journal article | ||
| Year | 2014 | Publication | Physical chemistry, chemical physics | Abbreviated Journal | Phys Chem Chem Phys |
| Volume | 16 | Issue | 40 | Pages | 22299-22308 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT) | ||||
| Abstract | We have performed a first-principles study of the p- and n-type conductivity in CuIn1−xGaxSe2 due to native point defects, based on the HSE06 hybrid functional. Band alignment shows that the band gap becomes larger with x due to the increasing conduction band minimum, rendering it hard to establish n-type conductivity in CuGaSe2. From the defect formation energies, we find that In/GaCu is a shallow donor, while VCu, VIn/Ga and CuIn/Ga act as shallow acceptors. Using the total charge neutrality of ionized defects and intrinsic charge carriers to determine the Fermi level, we show that under In-rich growth conditions InCu causes strongly n-type conductivity in CuInSe2. Under increasingly In-poor growth conditions, the conductivity type in CuInSe2 alters to p-type and compensation of the acceptors by InCu reduces, as also observed in photoluminescence experiments. In CuGaSe2, the native acceptors pin the Fermi level far away from the conduction band minimum, thus inhibiting n-type conductivity. On the other hand, CuGaSe2 shows strong p-type conductivity under a wide range of Ga-poor growth conditions. Maximal p-type conductivity in CuIn1−xGaxSe2 is reached under In/Ga-poor growth conditions, in agreement with charge concentration measurements on samples with In/Ga-poor stoichiometry, and is primarily due to the dominant acceptor CuIn/Ga. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Cambridge | Editor | ||
| Language | Wos | 000343072800042 | Publication Date | 2014-09-05 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1463-9076;1463-9084; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.123 | Times cited | 43 | Open Access | |
| Notes | ; We gratefully acknowledge financial support from the science fund FWO-Flanders through project G.0150.13. The first-principles calculations have been carried out on the HPC infrastructure of the University of Antwerp (CalcUA), a division of the Flemish Supercomputer Centre (VSC), supported financially by the Hercules foundation and the Flemish Government (EWI Department). We also like to thank Prof. S. Siebentritt of the University of Luxembourg for a presentation of her work on GIGS during a visit to our research group and for helpful discussions of our results. ; | Approved | Most recent IF: 4.123; 2014 IF: 4.493 | ||
| Call Number | UA @ lucian @ c:irua:120465 | Serial | 2284 | ||
| Permanent link to this record | |||||
| Author |
Bekaert, J.; Petrov, M.; Aperis, A.; Oppeneer, P.M.; Milošević, M.V. | ||||
| Title | Hydrogen-induced high-temperature superconductivity in two-dimensional materials : the example of hydrogenated monolayer MgB2 | Type | A1 Journal article | ||
| Year | 2019 | Publication | Physical review letters | Abbreviated Journal | Phys Rev Lett |
| Volume | 123 | Issue | 7 | Pages | 077001 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | Hydrogen-based compounds under ultrahigh pressure, such as the polyhydrides H3S and LaH10, superconduct through the conventional electron-phonon coupling mechanism to attain the record critical temperatures known to date. Here we exploit the intrinsic advantages of hydrogen to strongly enhance phonon-mediated superconductivity in a completely different system, namely, a two-dimensional material with hydrogen adatoms. We find that van Hove singularities in the electronic structure, originating from atomiclike hydrogen states, lead to a strong increase of the electronic density of states at the Fermi level, and thus of the electron-phonon coupling. Additionally, the emergence of high-frequency hydrogen-related phonon modes in this system boosts the electron-phonon coupling further. As a concrete example, we demonstrate the effect of hydrogen adatoms on the superconducting properties of monolayer MgB2, by solving the fully anisotropic Eliashberg equations, in conjunction with a first-principles description of the electronic and vibrational states, and their coupling. We show that hydrogenation leads to a high critical temperature of 67 K, which can be boosted to over 100 K by biaxial tensile strain. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000480611900017 | Publication Date | 2019-08-14 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0031-9007 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 8.462 | Times cited | 42 | Open Access | |
| Notes | ; This work was supported by TOPBOF-UAntwerp, Research Foundation-Flanders (FWO), the Swedish Research Council (VR), the Rontgen-Angstrom Cluster, and the EU-COST Action CA16218. J.B. acknowledges support of a postdoctoral fellowship of the FWO. The computational resources and services used for the first principles calculations in this work were provided by the VSC (Flemish Supercomputer Center), funded by the FWO and the Flemish Government-department EWI. Eliashberg theory calculations were supported through the Swedish National Infrastructure for Computing (SNIC). We would also like to acknowledge useful discussions with Bart Partoens, Jacques Tempere, and Matthieu Verstraete. ; | Approved | Most recent IF: 8.462 | ||
| Call Number | UA @ admin @ c:irua:161816 | Serial | 5415 | ||
| Permanent link to this record | |||||
| Author |
Bekaert, J.; Khestanova, E.; Hopkinson, D.G.; Birkbeck, J.; Clark, N.; Zhu, M.; Bandurin, D.A.; Gorbachev, R.; Fairclough, S.; Zou, Y.; Hamer, M.; Terry, D.J.; Peters, J.J.P.; Sanchez, A.M.; Partoens, B.; Haigh, S.J.; Milošević, M.V.; Grigorieva, I., V | ||||
| Title | Enhanced superconductivity in few-layer TaS₂ due to healing by oxygenation | Type | A1 Journal article | ||
| Year | 2020 | Publication | Nano Letters | Abbreviated Journal | Nano Lett |
| Volume | 20 | Issue | 5 | Pages | 3808-3818 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) | ||||
| Abstract | When approaching the atomically thin limit, defects and disorder play an increasingly important role in the properties of two-dimensional (2D) materials. While defects are generally thought to negatively affect superconductivity in 2D materials, here we demonstrate the contrary in the case of oxygenation of ultrathin tantalum disulfide (TaS2). Our first-principles calculations show that incorporation of oxygen into the TaS2 crystal lattice is energetically favorable and effectively heals sulfur vacancies typically present in these crystals, thus restoring the electronic band structure and the carrier density to the intrinsic characteristics of TaS2. Strikingly, this leads to a strong enhancement of the electron-phonon coupling, by up to 80% in the highly oxygenated limit. Using transport measurements on fresh and aged (oxygenated) few-layer TaS2, we found a marked increase of the superconducting critical temperature (T-c) upon aging, in agreement with our theory, while concurrent electron microscopy and electron-energy loss spectroscopy confirmed the presence of sulfur vacancies in freshly prepared TaS2 and incorporation of oxygen into the crystal lattice with time. Our work thus reveals the mechanism by which certain atomic-scale defects can be beneficial to superconductivity and opens a new route to engineer T-c in ultrathin materials. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000535255300114 | Publication Date | 2020-04-20 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1530-6984 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 10.8 | Times cited | 16 | Open Access | |
| Notes | ; This work was supported by Research Foundation-Flanders (FWO). J.Be. acknowledges support of a postdoctoral fellowship of the FWO. The computational resources and services used for the first-principles calculations in this work were provided by the VSC (Flemish Supercomputer Center), funded by the FWO and the Flemish Government-department EWI. S.J.H., D.H., and S.F. would like to thank the Engineering and Physical Sciences Research Council (EPSRC) U.K (grants EP/R031711/1, EP/P009050/1 and the Graphene NOWNANO CDT) and the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program (grant agreement ERC-2016-STG-EvoluTEM-715502, the Hetero2D Synergy grant and EC-FET Graphene Flagship) for funding. We thank Diamond Light Source for access and support in use of the electron Physical Science Imaging Centre (Instrument E02 and proposal numbers EM19315 and MG21597) that contributed to the results presented here. ; | Approved | Most recent IF: 10.8; 2020 IF: 12.712 | ||
| Call Number | UA @ admin @ c:irua:170264 | Serial | 6507 | ||
| Permanent link to this record | |||||
| Author |
Bekaert, J.; Bringmans, L.; Milošević, M.V. | ||||
| Title | Ginzburg-Landau surface energy of multiband superconductors : derivation and application to selected systems | Type | A1 Journal article | ||
| Year | 2023 | Publication | Journal of physics : condensed matter | Abbreviated Journal | |
| Volume | 35 | Issue | 32 | Pages | 325602-325610 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | We determine the energy of an interface between a multiband superconducting and a normal half-space, in presence of an applied magnetic field, based on a multiband Ginzburg-Landau (GL) approach. We obtain that the multiband surface energy is fully determined by the critical temperature, electronic densities of states, and superconducting gap functions associated with the different band condensates. This furthermore yields an expression for the thermodynamic critical magnetic field, in presence of an arbitrary number of contributing bands. Subsequently, we investigate the sign of the surface energy as a function of material parameters, through numerical solution of the GL equations. Here, we consider two distinct cases: (i) standard multiband superconductors with attractive interactions, and (ii) a three-band superconductor with a chiral ground state with phase frustration, arising from repulsive interband interactions. Furthermore, we apply this approach to several prime examples of multiband superconductors, such as metallic hydrogen and MgB2, based on microscopic parameters obtained from first-principles calculations. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000986281900001 | Publication Date | 2023-05-03 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0953-8984 | ISBN | Additional Links | UA library record; WoS full record | |
| Impact Factor | 2.7 | Times cited | Open Access | OpenAccess | |
| Notes | Approved | Most recent IF: 2.7; 2023 IF: 2.649 | |||
| Call Number | UA @ admin @ c:irua:196664 | Serial | 8875 | ||
| Permanent link to this record | |||||
| Author |
Bekaert, J.; Bignardi, L.; Aperis, A.; van Abswoude, P.; Mattevi, C.; Gorovikov, S.; Petaccia, L.; Goldoni, A.; Partoens, B.; Oppeneer, P.M.; Peeters, F.M.; Milošević, M.V.; Rudolf, P.; Cepek, C. | ||||
| Title | Free surfaces recast superconductivity in few-monolayer MgB2 : combined first-principles and ARPES demonstration | Type | A1 Journal article | ||
| Year | 2017 | Publication | Scientific reports | Abbreviated Journal | Sci Rep-Uk |
| Volume | 7 | Issue | Pages | 14458 | |
| Keywords | A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT) | ||||
| Abstract | <script type='text/javascript'>document.write(unpmarked('Two-dimensional materials are known to harbour properties very different from those of their bulk counterparts. Recent years have seen the rise of atomically thin superconductors, with a caveat that superconductivity is strongly depleted unless enhanced by specific substrates, intercalants or adatoms. Surprisingly, the role in superconductivity of electronic states originating from simple free surfaces of two-dimensional materials has remained elusive to date. Here, based on first-principles calculations, anisotropic Eliashberg theory, and angle-resolved photoemission spectroscopy (ARPES), we show that surface states in few-monolayer MgB2 make a major contribution to the superconducting gap spectrum and density of states, clearly distinct from the widely known, bulk-like sigma-and pi-gaps. As a proof of principle, we predict and measure the gap opening on the magnesium-based surface band up to a critical temperature as high as similar to 30 K for merely six monolayers thick MgB2. These findings establish free surfaces as an unavoidable ingredient in understanding and further tailoring of superconductivity in atomically thin materials.')); | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Nature Publishing Group | Place of Publication | London | Editor | |
| Language | Wos | 000414231000059 | Publication Date | 2017-10-25 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2045-2322 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 4.259 | Times cited | 27 | Open Access | |
| Notes | ; This work was supported by TOPBOF-UAntwerp, Research Foundation Flanders (FWO), the Foundation for Fundamental Research on Matter (FOM)-part of the Netherlands Organisation for Scientific Research, the Swedish Research Council (VR) and the Rontgen-Angstrom Cluster. P.v.A. acknowledges an Ubbo Emmius fellowship for his PhD studies. The computational resources and services used for the first-principles calculations in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Research Foundation Flanders (FWO) and the Flemish Government – department EWI. Eliashberg theory calculations were supported through the Swedish National Infrastructure for Computing (SNIC). We thank D. Lonza for technical assistance in the experimental part. ; | Approved | Most recent IF: 4.259 | ||
| Call Number | UA @ lucian @ c:irua:147426 | Serial | 4875 | ||
| Permanent link to this record | |||||
| Author |
Bekaert, J.; Aperis, A.; Partoens, B.; Oppeneer, P.M.; Milošević, M.V. | ||||
| Title | Evolution of multigap superconductivity in the atomically thin limit : strain-enhanced three-gap superconductivity in monolayer MgB2 | Type | A1 Journal article | ||
| Year | 2017 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
| Volume | 96 | Issue | 9 | Pages | 094510 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | Starting from first principles, we show the formation and evolution of superconducting gaps in MgB2 at its ultrathin limit. Atomically thin MgB2 is distinctly different from bulk MgB2 in that surface states become comparable in electronic density to the bulklike sigma and pi bands. Combining the ab initio electron-phonon coupling with the anisotropic Eliashberg equations, we showthat monolayer MgB2 develops three distinct superconducting gaps, on completely separate parts of the Fermi surface due to the emergent surface contribution. These gaps hybridize nontrivially with every extra monolayer added to the film owing to the opening of additional coupling channels. Furthermore, we reveal that the three-gap superconductivity in monolayer MgB2 is robust over the entire temperature range that stretches up to a considerably high critical temperature of 20 K. The latter can be boosted to >50K under biaxial tensile strain of similar to 4%, which is an enhancement that is stronger than in any other graphene-related superconductor known to date. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | American Physical Society | Place of Publication | New York, N.Y | Editor | |
| Language | Wos | 000410166800008 | Publication Date | 2017-09-11 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2469-9969; 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 56 | Open Access | |
| Notes | ; This work was supported by TOPBOF-UAntwerp, Research Foundation-Flanders (FWO), the Swedish Research Council (VR), and the Rontgen-Angstrom Cluster. The first-principles calculations have been carried out on the HPC infrastructure of the University of Antwerp (CalcUA), a division of the Flemish Supercomputer Centre (VSC), supported financially by the Hercules Foundation and the Flemish Government (EWI Department). Eliashberg theory calculations were supported through the Swedish National Infrastructure for Computing (SNIC). ; | Approved | Most recent IF: 3.836 | ||
| Call Number | UA @ lucian @ c:irua:145623 | Serial | 4741 | ||
| Permanent link to this record | |||||
| Author |
Bekaert, J.; Aperis, A.; Partoens, B.; Oppeneer, P.M.; Milošević, M.V. | ||||
| Title | Advanced first-principles theory of superconductivity including both lattice vibrations and spin fluctuations : the case of FeB4 | Type | A1 Journal article | ||
| Year | 2018 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
| Volume | 97 | Issue | 1 | Pages | 014503 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | <script type='text/javascript'>document.write(unpmarked('We present an advanced method to study spin fluctuations in superconductors quantitatively and entirely from first principles. This method can be generally applied to materials where electron-phonon coupling and spin fluctuations coexist. We employ it here to examine the recently synthesized superconductor iron tetraboride (FeB4) with experimental T-c similar to 2.4 K [H. Gou et al., Phys. Rev. Lett, 111, 157002 (2013)]. We prove that FeB4 is particularly prone to ferromagnetic spin fluctuations due to the presence of iron, resulting in a large Stoner interaction strength, I = 1.5 eV, as calculated from first principles. The other important factor is its Fermi surface that consists of three separate sheets, among which two are nested ellipsoids. The resulting susceptibility has a ferromagnetic peak around q = 0, from which we calculated the repulsive interaction between Cooper pair electrons using the random phase approximation. Subsequently, we combined the electron-phonon interaction calculated from first principles with the spin fluctuation interaction in fully anisotropic Eliashberg theory calculations. We show that the resulting superconducting gap spectrum is conventional, yet very strongly depleted due to coupling to the spin fluctuations. The critical temperature decreases from T-c = 41 K, if they are not taken into account, to T-c = 1.7 K, in good agreement with the experimental value.')); | ||||
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| Corporate Author | Thesis | ||||
| Publisher | American Physical Society | Place of Publication | New York, N.Y | Editor | |
| Language | Wos | 000419229100004 | Publication Date | 2018-01-04 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2469-9969; 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 23 | Open Access | |
| Notes | ; This work was supported by TOPBOF-UAntwerp, Research Foundation Flanders (FWO), the Swedish Research Council (VR), and the Rontgen-Angstrom Cluster. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Research Foundation Flanders (FWO) and the Flemish Government-department EWI. Anisotropic Eliashberg theory calculations were supported through the Swedish National Infrastructure for Computing (SNIC). ; | Approved | Most recent IF: 3.836 | ||
| Call Number | UA @ lucian @ c:irua:148447UA @ admin @ c:irua:148447 | Serial | 4866 | ||
| Permanent link to this record | |||||
| Author |
Bekaert, J. | ||||
| Title | Phonon-mediated superconductivity in ternary silicides X₄ CoSi (X = Nb, Ta) | Type | A1 Journal article | ||
| Year | 2023 | Publication | Physical review B | Abbreviated Journal | |
| Volume | 108 | Issue | 13 | Pages | 134504-134507 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | The superconducting properties of two recently synthesized ternary silicides with unit formula X<sub>4</sub>CoSi (X = Nb, Ta) are investigated through ab initio calculations combined with Eliashberg theory. Interestingly, their crystal structure comprises interlocking honeycomb networks of Nb/Ta atoms. Nb<sub>4</sub>CoSi is found to harbor better conditions for phonon-mediated superconductivity, as it possesses a higher density of states at the Fermi level, fostering stronger electron-phonon coupling. The superconducting critical temperatures (T<sub>c</sub>) follow the same trend, with Nb<sub>4</sub>CoSi having a twice higher value than Ta<sub>4</sub>CoSi. Furthermore, the calculated T<sub>c</sub> values (5.9 K vs 3.1 K) agree excellently with the experimentally obtained ones, establishing superconductivity in this new materials class as mediated by the electron-phonon coupling. Furthermore, my calculations show that the superconducting properties of these compounds do not simply correlate with the parameters of their honeycomb networks, contrary to proposals raised in the literature. Rather, their complete fermiology and phonon spectrum should be taken into account in order to explain their respective superconducting properties. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 001140080300003 | Publication Date | 2023-10-17 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2469-9969; 2469-9950 | ISBN | Additional Links | UA library record; WoS full record | |
| Impact Factor | 3.7 | Times cited | Open Access | ||
| Notes | Approved | Most recent IF: 3.7; 2023 IF: 3.836 | |||
| Call Number | UA @ admin @ c:irua:201445 | Serial | 9071 | ||
| Permanent link to this record | |||||
| Author |
Beheshtian, J.; Sadeghi, A.; Neek-Amal, M.; Michel, K.H.; Peeters, F.M. | ||||
| Title | Induced polarization and electronic properties of carbon-doped boron nitride nanoribbons | Type | A1 Journal article | ||
| Year | 2012 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
| Volume | 86 | Issue | 19 | Pages | 195433-195438 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | The electronic properties of boron nitride nanoribbons (BNNRs) doped with a line of carbon atoms are investigated using density functional calculations. By replacing a line of alternating B and N atoms with carbons, three different configurations are possible depending on the type of the atoms which bond to the carbons. We found very different electronic properties for these configurations: (i) the NCB arrangement is strongly polarized with a large dipole moment having an unexpected direction, (ii) the BCB and NCN arrangements are nonpolar with zero dipole moment, (iii) the doping by a carbon line reduces the band gap regardless of the local arrangement of the borons and the nitrogens around the carbon line, and (iv) the polarization and energy gap of the carbon-doped BNNRs can be tuned by an electric field applied parallel to the carbon line. Similar effects were found when either an armchair or zigzag line of carbon was introduced. | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Wos | 000311694200006 | Publication Date | 2012-11-29 | |
| 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 | 41 | Open Access | |
| Notes | ; We would like to thank J. M. Pereira and S. Goedecker for helpful discussions. This work was supported by the Flemish Science Foundation (FWO-Vl), the ESF-EuroGRAPHENE project CONGRAN. M. N.-A is supported by EU-Marie Curie IIF postdoc Fellowship/299522. ; | Approved | Most recent IF: 3.836; 2012 IF: 3.767 | ||
| Call Number | UA @ lucian @ c:irua:105136 | Serial | 1603 | ||
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| Author |
Behera, B.C.; Jana, S.; Bhat, S.G.; Gauquelin, N.; Tripathy, G.; Kumar, P.S.A.; Samal, D. | ||||
| Title | Evidence for exchange bias coupling at the perovskite/brownmillerite interface in spontaneously stabilized SrCoO3-\delta/SrCoO2.5 bilayers | Type | A1 Journal article | ||
| Year | 2019 | Publication | Physical review B | Abbreviated Journal | Phys Rev B |
| Volume | 99 | Issue | 2 | Pages | 024425 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Interface effect in complex oxide thin-film heterostructures lies at the vanguard of current research to design technologically relevant functionality and explore emergent physical phenomena. While most of the previous works focus on the perovskite/perovskite heterostructures, the study of perovskite/brownmillerite interfaces remains in its infancy. Here, we investigate spontaneously stabilized perovskite-ferromagnet (SrCoO3-delta)/brownmillerite-antiferromagnet (SrCoO2.5) bilayer with T-N > T-C and discover an unconventional interfacial magnetic exchange bias effect. From magnetometry investigations, it is rationalized that the observed effect stems from the interfacial ferromagnet/antiferromagnet coupling. The possibility for coupled ferromagnet/spin-glass interface engendering such effect is ruled out. Strikingly, a finite coercive field persists in the paramagnetic state of SrCoO3-delta,whereas the exchange bias field vanishes at T-C . We conjecture the observed effect to be due to the effective external quenched staggered field provided by the antiferromagnetic layer for the ferromagnetic spins at the interface. Our results not only unveil a paradigm to tailor the interfacial magnetic properties in oxide heterostructures without altering the cations at the interface, but also provide a purview to delve into the fundamental aspects of exchange bias in such unusual systems, paving a big step forward in thin-film magnetism. | ||||
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| Language | Wos | 000456481900003 | Publication Date | 2019-01-23 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2469-9969; 2469-9950 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.836 | Times cited | 2 | Open Access | OpenAccess |
| Notes | ; We are grateful to Sachin Sarangi for his superb technical support during magnetic measurements. We thank Gopal Pradhan for fruitful discussion. We thank Zhicheng Zhong for reading the manuscript and for suggestions. We thank T. Som for extending laboratory facility. D.S. and B.C.B. acknowledge the financial support from Max-Planck Society through Max Planck Partner Group. S.G.B. acknowledges the INSPIRE Faculty Fellowship Programme (DSTO1899) for the financial support. ; | Approved | Most recent IF: 3.836 | ||
| Call Number | UA @ admin @ c:irua:157562 | Serial | 5248 | ||
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| Author |
Bedanov, V.M.; Peeters, F.M. | ||||
| Title | Ordering and phase transitions of charged particles in a classical finite two-dimensional system | Type | A1 Journal article | ||
| Year | 1994 | Publication | Physical review : B : condensed matter and materials physics | Abbreviated Journal | Phys Rev B |
| Volume | 49 | Issue | Pages | 2667-2676 | |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
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| Publisher | Place of Publication | Lancaster, Pa | Editor | ||
| Language | Wos | A1994MV08900040 | Publication Date | 0000-00-00 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1098-0121; 0163-1829 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.736 | Times cited | 412 | Open Access | |
| Notes | Approved | no | |||
| Call Number | UA @ lucian @ c:irua:9366 | Serial | 2505 | ||
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| Author |
Beckwee, E.J.; Watson, G.; Houlleberghs, M.; Arenas Esteban, D.; Bals, S.; Van Der Voort, P.; Breynaert, E.; Martens, J.; Baron, G.V.; Denayer, J.F.M. | ||||
| Title | Enabling hydrate-based methane storage under mild operating conditions by periodic mesoporous organosilica nanotubes | Type | A1 Journal article | ||
| Year | 2023 | Publication | Heliyon | Abbreviated Journal | |
| Volume | 9 | Issue | 7 | Pages | e17662-14 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Biomethane is a renewable natural gas substitute produced from biogas. Storage of this sustainable energy vector in confined clathrate hydrates, encapsulated in the pores of a host material, is a highly promising avenue to improve storage capacity and energy efficiency. Herein, a new type of periodic mesoporous organosilica (PMO) nanotubes, referred to as hollow ring PMO (HR-PMO), capable of promoting methane clathrate hydrate formation under mild working conditions (273 K, 3.5 MPa) and at high water loading (5.1 g water/g HR-PMO) is reported. Gravimetric uptake measurements reveal a steep single-stepped isotherm and a noticeably high methane storage capacity (0.55 g methane/g HR-PMO; 0.11 g methane/g water at 3.5 MPa). The large working capacity throughout consecutive pressure-induced clathrate hydrate formationdissociation cycles demonstrates the material's excellent recyclability (97% preservation of capacity). Supported by ex situ cryo-electron tomography and x-ray diffraction, HR-PMO nanotubes are hypothesized to promote clathrate hydrate nucleation and growth by distribution and confinement of water in the mesopores of their outer wall, along the central channels of the nanotubes and on the external nanotube surface. These findings showcase the potential for application of organosilica materials with hierarchical and interconnected pore systems for pressure-based storage of biomethane in confined clathrate hydrates. | ||||
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| Language | Wos | 001056264100001 | Publication Date | 2023-06-28 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2405-8440 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | Times cited | 4 | Open Access | OpenAccess | |
| Notes | E.J.B., G.W. and M.H. contributed equally to this work. M.H. acknowledges FWO for an FWO-SB fellowship. All authors acknowledge VLAIO for Moonshot funding (ARCLATH, n ? HBC.2019.0110, ARCLATH2, n ? HBC.2021.0254) . J.A.M. acknowledges the Flemish Government for long-term structural funding (Methusalem) and department EWI for infrastructure investment via the Hermes Fund (AH.2016.134) . NMRCoRe acknowledges the Flemish government, department EWI for financial support as International Research Infrastructure (I001321N: Nuclear Magnetic Resonance Spectroscopy Platform for Molecular Water Research) . J.A.M. acknowledges the European Research Council (ERC) for an Advanced Research Grant under the European Union's Horizon 2020 research and innovation program under grant agreement No. 834134 (WATUSO) . S.B acknowledges financial support by the Research Foundation Flanders (FWO grant G.0381.16N) . This project also received funding from the European Union's Horizon 2020 research and innovation program under grant agreement No 731019 (EUSMI) and No 815128 (REALNANO) . | Approved | Most recent IF: NA | ||
| Call Number | UA @ admin @ c:irua:199249 | Serial | 8862 | ||
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| Author |
Beckers, A.; Thewissen, M.; Sorée, B. | ||||
| Title | Energy filtering in silicon nanowires and nanosheets using a geometric superlattice and its use for steep-slope transistors | Type | A1 Journal article | ||
| Year | 2018 | Publication | Journal of applied physics | Abbreviated Journal | J Appl Phys |
| Volume | 124 | Issue | 14 | Pages | 144304 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | This paper investigates energy filtering in silicon nanowires and nanosheets by resonant electron tunneling through a geometric superlattice. A geometric superlattice is any kind of periodic geometric feature along the transport direction of the nanowire or nanosheet. Multivalley quantum-transport simulations are used to demonstrate the manifestation of minibands and minibandgaps in the transmission spectra of such a superlattice. We find that the presence of different valleys in the conduction band of silicon favors a nanowire with a rectangular cross section for effective energy filtering. The obtained energy filter can consequently be used in the source extension of a field-effect transistor to prevent high-energy electrons from contributing to the leakage current. Self-consistent Schrodinger-Poisson simulations in the ballistic limit show minimum subthreshold swings of 6 mV/decade for geometric superlattices with indentations. The obtained theoretical performance metrics for the simulated devices are compared with conventional III-V superlatticeFETs and TunnelFETs. The adaptation of the quantum transmitting boundary method to the finite-element simulation of 3-D structures with anisotropic effective mass is presented in Appendixes A and B. Our results bare relevance in the search for steep-slope transistor alternatives which are compatible with the silicon industry and can overcome the power-consumption bottleneck inherent to standard CMOS technologies. Published by AIP Publishing. | ||||
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| Publisher | American Institute of Physics | Place of Publication | New York, N.Y. | Editor | |
| Language | Wos | 000447148100011 | Publication Date | 2018-10-11 | |
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| Series Volume | Series Issue | Edition | |||
| ISSN | 0021-8979; 1089-7550 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.068 | Times cited | 3 | Open Access | |
| Notes | ; ; | Approved | Most recent IF: 2.068 | ||
| Call Number | UA @ lucian @ c:irua:154729UA @ admin @ c:irua:154729 | Serial | 5099 | ||
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| Author |
Becker, T.; Nelissen, K.; Cleuren, B.; Partoens, B.; Van den Broeck, C. | ||||
| Title | Adsorption and desorption in confined geometries : a discrete hopping model | Type | A1 Journal article | ||
| Year | 2014 | Publication | The European physical journal. Special topics | Abbreviated Journal | Eur Phys J-Spec Top |
| Volume | 223 | Issue | 14 | Pages | 3243-3256 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT) | ||||
| Abstract | We study the adsorption and desorption kinetics of interacting particles moving on a one-dimensional lattice. Confinement is introduced by limiting the number of particles on a lattice site. Adsorption and desorption are found to proceed at different rates, and are strongly influenced by the concentration-dependent transport diffusion. Analytical solutions for the transport and self-diffusion are given for systems of length 1 and 2 and for a zero-range process. In the last situation the self- and transport diffusion can be calculated analytically for any length. | ||||
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| Language | Wos | 000346416400015 | Publication Date | 2014-12-15 | |
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| ISSN | 1951-6355;1951-6401; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 1.862 | Times cited | 4 | Open Access | |
| Notes | ; This work was supported by the Flemish Science Foundation (FWO-Vlaanderen). The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center), funded by the Hercules Foundation and the Flemish Government – department EWI. ; | Approved | Most recent IF: 1.862; 2014 IF: 1.399 | ||
| Call Number | UA @ lucian @ c:irua:122779 | Serial | 61 | ||
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