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Author Chaney, G.; Cakir, D.; Peeters, F.M.; Ataca, C.
Title Stability of adsorption of Mg and Na on sulfur-functionalized MXenes Type A1 Journal article
Year 2021 Publication Physical Chemistry Chemical Physics Abbreviated Journal Phys Chem Chem Phys
Volume 23 Issue 44 Pages 25424-25433
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Two-dimensional materials composed of transition metal carbides and nitrides (MXenes) are poised to revolutionize energy conversion and storage. In this work, we used density functional theory (DFT) to investigate the adsorption of Mg and Na adatoms on five M2CS2 monolayers (where M = Mo, Nb, Ti, V, and Zr) for battery applications. We assessed the stability of the adatom (i.e. Na and Mg)-monolayer systems by calculating adsorption and formation energies, as well as voltages as a function of surface coverage. For instance, we found that Mo2CS2 cannot support a full layer of Na nor even a single Mg atom. Na and Mg exhibit the strongest binding on Zr2CS2, followed by Ti2CS2, Nb2CS2 and V2CS2. Using the nudged elastic band method (NEB), we computed promising diffusion barriers for both dilute and nearly full ion surface coverage cases. In the dilute ion adsorption case, a single Mg and Na atom on Ti2CS2 experience similar to 0.47 eV and similar to 0.10 eV diffusion barriers between the lowest energy sites, respectively. For a nearly full surface coverage, a Na ion moving on Ti2CS2 experiences a similar to 0.33 eV energy barrier, implying a concentration-dependent diffusion barrier. Our molecular dynamics results indicate that the three (one) layers (layer) of the Mg (Na) ion on both surfaces of Ti2CS2 remain stable at T = 300 K. While, according to voltage calculations, Zr2CS2 can store Na up to three atomic layers, our MD simulations predict that the outermost layers detach from the Zr2CS2 monolayer due to the weak interaction between Na ions and the monolayer. This suggests that MD simulations are essential to confirm the stability of an ion-electrode system – an insight that is mostly absent in previous studies.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000716024400001 Publication Date 2021-10-22
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 7 Open Access Not_Open_Access
Notes Approved (up) Most recent IF: 4.123
Call Number UA @ admin @ c:irua:184075 Serial 7020
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Author Nazar, N.D.; Vazifehshenas, T.; Ebrahimi, M.R.; Peeters, F.M.
Title Strong anisotropic optical properties of 8-Pmmn borophene : a many-body perturbation study Type A1 Journal article
Year 2021 Publication Physical Chemistry Chemical Physics Abbreviated Journal Phys Chem Chem Phys
Volume 23 Issue 30 Pages 16417-16422
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Using first-principles many-body perturbation theory, we investigate the optical properties of 8-Pmmn borophene at two levels of approximations; the GW method considering only the electron-electron interaction and the GW in combination with the Bethe-Salpeter equation including electron-hole coupling. The band structure exhibits anisotropic Dirac cones with semimetallic character. The optical absorption spectra are obtained for different light polarizations and we predict strong optical absorbance anisotropy. The absorption peaks undergo a global redshift when the electron-hole interaction is taken into account due to the formation of bound excitons which have an anisotropic excitonic wave function.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000677722700001 Publication Date 2021-07-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1463-9076; 1463-9084 ISBN Additional Links UA library record; WoS full record
Impact Factor 4.123 Times cited 4 Open Access Not_Open_Access
Notes Approved (up) Most recent IF: 4.123
Call Number UA @ admin @ c:irua:180385 Serial 7022
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Author Faraji, M.; Bafekry, A.; Fadlallah, M.M.; Molaei, F.; Hieu, N.N.; Qian, P.; Ghergherehchi, M.; Gogova, D.
Title Surface modification of titanium carbide MXene monolayers (Ti₂C and Ti₃C₂) via chalcogenide and halogenide atoms Type A1 Journal article
Year 2021 Publication Physical Chemistry Chemical Physics Abbreviated Journal Phys Chem Chem Phys
Volume 23 Issue 28 Pages 15319-15328
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Inspired by the recent successful growth of Ti2C and Ti3C2 monolayers, here, we investigate the structural, electronic, and mechanical properties of functionalized Ti2C and Ti3C2 monolayers by means of density functional theory calculations. The results reveal that monolayers of Ti2C and Ti3C2 are dynamically stable metals. Phonon band dispersion calculations demonstrate that two-surface functionalization of Ti2C and Ti(3)C(2)via chalcogenides (S, Se, and Te), halides (F, Cl, Br, and I), and oxygen atoms results in dynamically stable novel functionalized monolayer materials. Electronic band dispersions and density of states calculations reveal that all functionalized monolayer structures preserve the metallic nature of both Ti2C and Ti3C2 except Ti2C-O-2, which possesses the behavior of an indirect semiconductor via full-surface oxygen passivation. In addition, it is shown that although halide passivated Ti3C2 structures are still metallic, there exist multiple Dirac-like cones around the Fermi energy level, which indicates that semi-metallic behavior can be obtained upon external effects by tuning the energy of the Dirac cones. In addition, the computed linear-elastic parameters prove that functionalization is a powerful tool in tuning the mechanical properties of stiff monolayers of bare Ti2C and Ti3C2. Our study discloses that the electronic and structural properties of Ti2C and Ti3C2 MXene monolayers are suitable for surface modification, which is highly desirable for material property engineering and device integration.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000672406800001 Publication Date 2021-06-23
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 Open Access OpenAccess
Notes Approved (up) Most recent IF: 4.123
Call Number UA @ admin @ c:irua:179809 Serial 7027
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Author Naseri, M.; Bafekry, A.; Faraji, M.; Hoat, D.M.; Fadlallah, M.M.; Ghergherehchi, M.; Sabbaghi, N.; Gogova, D.
Title Two-dimensional buckled tetragonal cadmium chalcogenides including CdS, CdSe, and CdTe monolayers as photo-catalysts for water splitting Type A1 Journal article
Year 2021 Publication Physical Chemistry Chemical Physics Abbreviated Journal Phys Chem Chem Phys
Volume 23 Issue 21 Pages 12226-12232
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Pure hydrogen production via water splitting is an ideal strategy for producing clean and sustainable energy. Two-dimensional (2D) cadmium chalcogenide single-layers with a tetragonal crystal structure, namely Tetra-CdX (X = S, Se, and Te) monolayers, are theoretically predicted by means of density functional theory (DFT). Their structural stability and electronic and optical properties are investigated. We find that Tetra-CdX single-layers are thermodynamically stable. Their stability decreases as we go down the 6A group in the periodic table, i.e., from X = S to Se, and Te which also means that the electronegativity decreases. All considered novel monolayers are indirect band gap semiconductors. Using the HSE06 functional the electronic band gaps of CdS, CdSe, and CdTe monolayers are predicted to be 3.10 eV, 2.97 eV, and 2.90 eV, respectively. The impact of mechanical strain on the physical properties was studied, which indicates that compressive strain increases the band gap and tensile strain decreases the band gap. The optical properties of the Tetra-CdX monolayers show the ability of these monolayers to absorb visible light. Due to the suitable band gaps and band edge positions of Tetra-CdX, these newly discovered 2D materials are promising for photocatalytic water splitting.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000651904600001 Publication Date 2021-04-30
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 Open Access Not_Open_Access
Notes Approved (up) Most recent IF: 4.123
Call Number UA @ admin @ c:irua:178378 Serial 7041
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Author Bafekry, A.; Karbasizadeh, S.; Stampfl, C.; Faraji, M.; Hoat, D.M.; Sarsari, I.A.; Feghhi, S.A.H.; Ghergherehchi, M.
Title Two-dimensional Janus semiconductor BiTeCl and BiTeBr monolayers : a first-principles study on their tunable electronic properties via an electric field and mechanical strain Type A1 Journal article
Year 2021 Publication Physical Chemistry Chemical Physics Abbreviated Journal Phys Chem Chem Phys
Volume 23 Issue 28 Pages 15216-15223
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Motivated by the recent successful synthesis of highly crystalline ultrathin BiTeCl and BiTeBr layered sheets [Debarati Hajra et al., ACS Nano, 2020, 14, 15626], herein for the first time, we carry out a comprehensive study on the structural and electronic properties of BiTeCl and BiTeBr Janus monolayers using density functional theory (DFT) calculations. Different structural and electronic parameters including the lattice constant, bond lengths, layer thickness in the z-direction, different interatomic angles, work function, charge density difference, cohesive energy and Rashba coefficients are determined to acquire a deep understanding of these monolayers. The calculations show good stability of the studied single layers. BiTeCl and BiTeBr monolayers are semiconductors with electronic bandgaps of 0.83 and 0.80 eV, respectively. The results also show that the semiconductor-metal transformation can be induced by increasing the number of layers. In addition, the engineering of the electronic structure is also studied by applying an electric field, and mechanical uniaxial and biaxial strain. The results show a significant change of the bandgaps and that an indirect-direct band-gap transition can be induced. This study highlights the positive prospect for the application of BiTeCl and BiTeBr layered sheets in novel electronic and energy conversion systems.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000670553900001 Publication Date 2021-06-16
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 Open Access OpenAccess
Notes Approved (up) Most recent IF: 4.123
Call Number UA @ admin @ c:irua:179827 Serial 7042
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Author Baskurt, M.; Nair, R.R.; Peeters, F.M.; Sahin, H.
Title Ultra-thin structures of manganese fluorides : conversion from manganese dichalcogenides by fluorination Type A1 Journal article
Year 2021 Publication Physical Chemistry Chemical Physics Abbreviated Journal Phys Chem Chem Phys
Volume 23 Issue 17 Pages 10218-10224
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract In this study, it is predicted by density functional theory calculations that graphene-like novel ultra-thin phases of manganese fluoride crystals, that have nonlayered structures in their bulk form, can be stabilized by fluorination of manganese dichalcogenide crystals. First, it is shown that substitution of fluorine atoms with chalcogens in the manganese dichalcogenide host lattice is favorable. Among possible crystal formations, three stable ultra-thin structures of manganese fluoride, 1H-MnF2, 1T-MnF2 and MnF3, are found to be stable by total energy optimization calculations. In addition, phonon calculations and Raman activity analysis reveal that predicted novel single-layers are dynamically stable crystal structures displaying distinctive characteristic peaks in their vibrational spectrum enabling experimental determination of the corresponding phases. Differing from 1H-MnF2 antiferromagnetic (AFM) large gap semiconductor, 1T-MnF2 and MnF3 single-layers are semiconductors with ferromagnetic (FM) ground state.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000641719700001 Publication Date 2021-04-15
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 1 Open Access Not_Open_Access
Notes Approved (up) Most recent IF: 4.123
Call Number UA @ admin @ c:irua:178252 Serial 7043
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Author Sozen, Y.; Yagmurcukardes, M.; Sahin, H.
Title Vibrational and optical identification of GeO₂ and GeO single layers : a first-principles study Type A1 Journal article
Year 2021 Publication Physical Chemistry Chemical Physics Abbreviated Journal Phys Chem Chem Phys
Volume 23 Issue 37 Pages 21307-21315
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract In the present work, the identification of two hexagonal phases of germanium oxides (namely GeO2 and GeO) through the vibrational and optical properties is reported using density functional theory calculations. While structural optimizations show that single-layer GeO2 and GeO crystallize in 1T and buckled phases, phonon band dispersions reveal the dynamical stability of each structure. First-order off-resonant Raman spectral predictions demonstrate that each free-standing single-layer possesses characteristic peaks that are representative for the identification of the germanium oxide phase. On the other hand, electronic band dispersion analysis shows the insulating and large-gap semiconducting nature of single-layer GeO2 and GeO, respectively. Moreover, optical absorption, reflectance, and transmittance spectra obtained by means of G(0)W(0)-BSE calculations reveal the existence of tightly bound excitons in each phase, displaying strong optical absorption. Furthermore, the excitonic gaps are found to be at deep UV and visible portions of the spectrum, for GeO2 and GeO crystals, with energies of 6.24 and 3.10 eV, respectively. In addition, at the prominent excitonic resonances, single-layers display high reflectivity with a zero transmittance, which is another indication of the strong light-matter interaction inside the crystal medium.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000697364300001 Publication Date 2021-09-02
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 Open Access Not_Open_Access
Notes Approved (up) Most recent IF: 4.123
Call Number UA @ admin @ c:irua:181571 Serial 7044
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Author Ao, Z.M.; Hernández-Nieves, A.D.; Peeters, F.M.; Li, S.
Title The electric field as a novel switch for uptake/release of hydrogen for storage in nitrogen doped graphene Type A1 Journal article
Year 2012 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys
Volume 14 Issue 4 Pages 1463-1467
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Nitrogen-doped graphene was recently synthesized and was reported to be a catalyst for hydrogen dissociative adsorption under a perpendicular applied electric field (F). In this work, the diffusion of H atoms on N-doped graphene, in the presence and absence of an applied perpendicular electric field, is studied using density functional theory. We demonstrate that the applied field can significantly facilitate the binding of hydrogen molecules on N-doped graphene through dissociative adsorption and diffusion on the surface. By removing the applied field the absorbed H atoms can be released efficiently. Our theoretical calculation indicates that N-doped graphene is a promising hydrogen storage material with reversible hydrogen adsorption/desorption where the applied electric field can act as a switch for the uptake/release processes.
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Corporate Author Thesis
Publisher Place of Publication Cambridge Editor
Language Wos 000298754500018 Publication Date 2011-11-21
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 67 Open Access
Notes ; Financial support of the Vice-Chancellor's Postdoctoral Research Fellowship Program (SIR50/PS19184) and the ECR grant (SIR30/PS24201) from the University of New South Wales are acknowledged. This work is also supported by the Flemish Science Foundation (FWO-Vl) and the Belgian Science Policy (IAP). ; Approved (up) Most recent IF: 4.123; 2012 IF: 3.829
Call Number UA @ lucian @ c:irua:96266 Serial 3578
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Author Verberck, B.; Okazaki, T.; Tarakina, N.V.
Title Ordered and disordered packing of coronene molecules in carbon nanotubes Type A1 Journal article
Year 2013 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys
Volume 15 Issue 41 Pages 18108-18114
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Monte Carlo simulations of coronene molecules in single-walled carbon nanotubes (SWCNTs) and dicoronylene molecules in SWCNTs are performed. Depending on the diameter D of the encapsulating SWCNT, regimes favoring the formation of ordered, one-dimensional (1D) stacks of tilted molecules (D <= 1.7 nm for coronene@SWCNT, 1.5 nm <= D <= 1.7 nm for dicoronylene@SWCNT) and regimes with disordered molecular arrangements and increased translational mobilities enabling the thermally induced polymerization of neighboring molecules resulting in the formation of graphene nanoribbons (GNRs) are observed. The results show that the diameter of the encapsulating nanotube is a crucial parameter for the controlled synthesis of either highly ordered 1D structures or GNR precursors.
Address
Corporate Author Thesis
Publisher Place of Publication Cambridge Editor
Language Wos 000325400600045 Publication Date 2013-09-05
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 9 Open Access
Notes ; B.V. is a Postdoctoral Fellow of the Research Foundation Flanders (FWO-VI). N.V.T. acknowledges funding by the Bavarian Ministry of Sciences, Research and the Arts. ; Approved (up) Most recent IF: 4.123; 2013 IF: 4.198
Call Number UA @ lucian @ c:irua:112212 Serial 2502
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Author Schoeters, B.; Neyts, E.C.; Khalilov, U.; Pourtois, G.; Partoens, B.
Title Stability of Si epoxide defects in Si nanowires : a mixed reactive force field/DFT study Type A1 Journal article
Year 2013 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys
Volume 15 Issue 36 Pages 15091-15097
Keywords A1 Journal article; Condensed Matter Theory (CMT); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Modeling the oxidation process of silicon nanowires through reactive force field based molecular dynamics simulations suggests that the formation of Si epoxide defects occurs both at the Si/SiOx interface and at the nanowire surface, whereas for flat surfaces, this defect is experimentally observed to occur only at the interface as a result of stress. In this paper, we argue that the increasing curvature stabilizes the defect at the nanowire surface, as suggested by our density functional theory calculations. The latter can have important consequences for the opto-electronic properties of thin silicon nanowires, since the epoxide induces an electronic state within the band gap. Removing the epoxide defect by hydrogenation is expected to be possible but becomes increasingly difficult with a reduction of the diameter of the nanowires.
Address
Corporate Author Thesis
Publisher Place of Publication Cambridge Editor
Language Wos 000323520600029 Publication Date 2013-07-16
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 3 Open Access
Notes ; BS gratefully acknowledges financial support of the IWT, Institute for the Promotion of Innovation by Science and Technology in Flanders, via the SBO project “SilaSol”. This work was carried out using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish government and the Universiteit Antwerpen. ; Approved (up) Most recent IF: 4.123; 2013 IF: 4.198
Call Number UA @ lucian @ c:irua:110793 Serial 3130
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Author Çakir, D.; Sahin, H.; Peeters, F.M.
Title Doping of rhenium disulfide monolayers : a systematic first principles study Type A1 Journal article
Year 2014 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys
Volume 16 Issue 31 Pages 16771-16779
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The absence of a direct-to-indirect band gap transition in ReS2 when going from the monolayer to bulk makes it special among the other semiconducting transition metal dichalcogenides. The functionalization of this promising layered material emerges as a necessity for the next generation technological applications. Here, the structural, electronic, and magnetic properties of substitutionally doped ReS2 monolayers at either the S or Re site were systematically studied by using first principles density functional calculations. We found that substitutional doping of ReS2 depends sensitively on the growth conditions of ReS2. Among the large number of non-metallic atoms, namely H, B, C, Se, Te, F, Br, Cl, As, P. and N, we identified the most promising candidates for n-type and p-type doping of ReS2. While Cl is an ideal candidate for n-type doping, P appears to be the most promising candidate for p-type doping of the ReS2 monolayer. We also investigated the doping of ReS2 with metal atoms, namely Mo, W, Ti, V. Cr, Co, Fe, Mn, Ni, Cu, Nb, Zn, Ru, Os and Pt. Mo, Nb, Ti, and V atoms are found to be easily incorporated in a single layer of ReS2 as substitutional impurities at the Re site for all growth conditions considered in this work. Tuning chemical potentials of dopant atoms energetically makes it possible to dope ReS2 with Fe, Co, Cr, Mn, W, Ru, and Os at the Re site. We observe a robust trend for the magnetic moments when substituting a Re atom with metal atoms such that depending on the electronic configuration of dopant atoms, the net magnetic moment of the doped ReS2 becomes either 0 or 1 mu(B). Among the metallic dopants, Mo is the best candidate for p-type doping of ReS2 owing to its favorable energetics and promising electronic properties.
Address
Corporate Author Thesis
Publisher Place of Publication Cambridge Editor
Language Wos 000340075700048 Publication Date 2014-07-02
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 58 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-VI) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure), and HPC infrastructure of the University of Antwerp (CalcUA) a division of the Flemish Supercomputer Center (VSC), which is funded by the Hercules foundation. H.S. is supported by a FWO Pegasus-long Marie Curie Fellowship. D.C. is supported by a FWO Pegasus-short Marie Curie Fellowship. ; Approved (up) Most recent IF: 4.123; 2014 IF: 4.493
Call Number UA @ lucian @ c:irua:118742 Serial 752
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Author Sarmadian, N.; Saniz, R.; Partoens, B.; Lamoen, D.; Volety, K.; Huyberechts, G.; Paul, J.
Title High throughput first-principles calculations of bixbyite oxides for TCO applications Type A1 Journal article
Year 2014 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys
Volume 16 Issue 33 Pages 17724-17733
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
Abstract We present a high-throughput computing scheme based on density functional theory (DFT) to generate a class of oxides and screen them with the aim of identifying those that might be electronically appropriate for transparent conducting oxide (TCO) applications. The screening criteria used are a minimum band gap to ensure sufficient transparency, a band edge alignment consistent with easy n- or p-type dopability, and a minimum thermodynamic phase stability to be experimentally synthesizable. Following this scheme we screened 23 binary and 1518 ternary bixbyite oxides in order to identify promising candidates, which can then be a subject of an in-depth study. The results for the known TCOs are in good agreement with the reported data in the literature. We suggest a list of several new potential TCOs, including both n- and p-type compounds.
Address
Corporate Author Thesis
Publisher Place of Publication Cambridge Editor
Language Wos 000341064800041 Publication Date 2014-07-07
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 23 Open Access
Notes ; We gratefully acknowledge financial support from the IWT-Vlaanderen through the ISIMADE project (IWT-n 080023), the FWO-Vlaanderen through project G.0150.13 and a GOA fund from the University of Antwerp. This work was carried out using the HPC infrastructure of the University of Antwerp (CalcUA) a division of the Flemish Supercomputer Center VSC, which is funded by the Hercules foundation and the Flemish Government (EWI Department). ; Approved (up) Most recent IF: 4.123; 2014 IF: 4.493
Call Number UA @ lucian @ c:irua:118263 Serial 1469
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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 (up) Most recent IF: 4.123; 2014 IF: 4.493
Call Number UA @ lucian @ c:irua:120465 Serial 2284
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Author Amini, M.N.; Dixit, H.; Saniz, R.; Lamoen, D.; Partoens, B.
Title The origin of p-type conductivity in ZnM2O4 (M = Co, Rh, Ir) spinels Type A1 Journal article
Year 2014 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys
Volume 16 Issue 6 Pages 2588-2596
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
Abstract ZnM2O4 (M = Co, Rh, Ir) spinels are considered as a class of potential p-type transparent conducting oxides (TCOs). We report the formation energy of acceptor-like defects using first principles calculations with an advanced hybrid exchange-correlation functional (HSE06) within density functional theory (DFT). Due to the discrepancies between the theoretically obtained band gaps with this hybrid functional and the – scattered – experimental results, we also perform GW calculations to support the validity of the description of these spinels with the HSE06 functional. The considered defects are the cation vacancy and antisite defects, which are supposed to be the leading source of disorder in the spinel structures. We also discuss the band alignments in these spinels. The calculated formation energies indicate that the antisite defects ZnM (Zn replacing M, M = Co, Rh, Ir) and VZn act as shallow acceptors in ZnCo2O4, ZnRh2O4 and ZnIr2O4, which explains the experimentally observed p-type conductivity in those systems. Moreover, our systematic study indicates that the ZnIr antisite defect has the lowest formation energy in the group and it corroborates the highest p-type conductivity reported for ZnIr2O4 among the group of ZnM2O4 spinels. To gain further insight into factors affecting the p-type conductivity, we have also investigated the formation of localized small polarons by calculating the self-trapping energy of the holes.
Address
Corporate Author Thesis
Publisher Place of Publication Cambridge Editor
Language Wos 000329926700040 Publication Date 2013-12-03
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 47 Open Access
Notes Fwo; Goa; Hercules Approved (up) Most recent IF: 4.123; 2014 IF: 4.493
Call Number UA @ lucian @ c:irua:114829 Serial 2525
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Author Brito, B.G.A.; Hai, G.-Q.; Teixeira Rabelo, J.N.; Cândido, L.
Title A quantum Monte Carlo study on electron correlation in all-metal aromatic clusters MAl4 – (M = Li, Na, K, Rb, Cu, Ag and Au) Type A1 Journal article
Year 2014 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys
Volume 16 Issue 18 Pages 8639-8645
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Using fixed-node diffusion quantum Monte Carlo (FN-DMC) simulation we investigate the electron correlation in all-metal aromatic clusters MAl4- (with M = Li, Na, K, Rb, Cu, Ag and Au). The electron detachment energies and electron affinities of the clusters are obtained. The vertical electron detachment energies obtained from the FN-DMC calculations are in very good agreement with the available experimental results. Calculations are also performed within the Hartree-Fock approximation, density-functional theory (DFT), and the couple-cluster (CCSD(T)) method. From the obtained results, we analyse the impact of the electron correlation effects in these bimetallic clusters and find that the correlation of the valence electrons contributes significantly to the detachment energies and electron affinities, varying between 20% and 50% of their total values. Furthermore, we discuss the electron correlation effects on the stability of the clusters as well as the accuracy of the DFT and CCSD(T) calculations in the present systems.
Address
Corporate Author Thesis
Publisher Place of Publication Cambridge Editor
Language Wos 000334602900052 Publication Date 2014-03-21
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 10 Open Access
Notes ; This research was supported by CNPq, FAPESP and FAPEG (Brazil). ; Approved (up) Most recent IF: 4.123; 2014 IF: 4.493
Call Number UA @ lucian @ c:irua:117247 Serial 2781
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Author Çakir, D.; Kecik, D.; Sahin, H.; Durgun, E.; Peeters, F.M.
Title Realization of a p-n junction in a single layer boron-phosphide Type A1 Journal article
Year 2015 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys
Volume 17 Issue 17 Pages 13013-13020
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Two-dimensional (2D) materials have attracted growing interest due to their potential use in the next generation of nanoelectronic and optoelectronic applications. On the basis of first-principles calculations based on density functional theory, we first investigate the electronic and mechanical properties of single layer boron phosphide (h-BP). Our calculations show that h-BP is a mechanically stable 2D material with a direct band gap of 0.9 eV at the K-point, promising for both electronic and optoelectronic applications. We next investigate the electron transport properties of a p-n junction constructed from single layer boron phosphide (h-BP) using the non-equilibrium Green's function formalism. The n-and p-type doping of BP are achieved by substitutional doping of B with C and P with Si, respectively. C(Si) substitutional doping creates donor (acceptor) states close to the conduction (valence) band edge of BP, which are essential to construct an efficient p-n junction. By modifying the structure and doping concentration, it is possible to tune the electronic and transport properties of the p-n junction which exhibits not only diode characteristics with a large current rectification but also negative differential resistance (NDR). The degree of NDR can be easily tuned via device engineering.
Address
Corporate Author Thesis
Publisher Place of Publication Cambridge Editor
Language Wos 000354195300065 Publication Date 2015-04-16
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 104 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl), the Methusalem foundation of the Flemish government and the Bilateral program FWO-TUBITAK (under the Project No. 113T050) between Flanders and Turkey. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure), and HPC infrastructure of the University of Antwerp (CalcUA) a division of the Flemish Supercomputer Center (VSC), which is funded by the Hercules foundation. D.C. is supported by a FWO Pegasus-short Marie Curie Fellowship. H.S. is supported by a FWO Pegasus Marie Curie-long Fellowship. E.D. acknowledges support from Bilim Akademisi – The Science Academy, Turkey under the BAGEP program. ; Approved (up) Most recent IF: 4.123; 2015 IF: 4.493
Call Number c:irua:126394 Serial 2835
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Author Amini, M.N.; Saniz, R.; Lamoen, D.; Partoens, B.
Title The role of the VZn-NO-H complex in the p-type conductivity in ZnO Type A1 Journal article
Year 2015 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys
Volume 17 Issue 17 Pages 5485-5489
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
Abstract Past research efforts aiming at obtaining stable p-type ZnO have been based on complexes involving nitrogen doping. A recent experiment by (J. G. Reynolds et al., Appl. Phys. Lett., 2013, 102, 152114) demonstrated a significant ([similar]1018 cm−3) p-type behavior in N-doped ZnO films after appropriate annealing. The p-type conductivity was attributed to a VZnNOH shallow acceptor complex, formed by a Zn vacancy (VZn), N substituting O (NO), and H interstitial (Hi). We present here a first-principles hybrid functional study of this complex compared to the one without hydrogen. Our results confirm that the VZnNOH complex acts as an acceptor in ZnO. We find that H plays an important role, because it lowers the formation energy of the complex with respect to VZnNO, a complex known to exhibit (unstable) p-type behavior. However, this additional H atom also occupies the hole level at the origin of the shallow behavior of VZnNO, leaving only two states empty higher in the band gap and making the VZnNOH complex a deep acceptor. Therefore, we conclude that the cause of the observed p-type conductivity in experiment is not the presence of the VZnNOH complex, but probably the formation of the VZnNO complex during the annealing process.
Address
Corporate Author Thesis
Publisher Place of Publication Cambridge Editor
Language Wos 000349616400080 Publication Date 2015-01-20
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 20 Open Access
Notes FWO G021614N; FWO G015013; FWO G018914N; GOA; Hercules Approved (up) Most recent IF: 4.123; 2015 IF: 4.493
Call Number c:irua:123218 Serial 3592
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Author Çakir, D.; Peeters, F.M.
Title Fluorographane : a promising material for bipolar doping of MoS2 Type A1 Journal article
Year 2015 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys
Volume 17 Issue 17 Pages 27636-27641
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Using first principles calculations we investigate the structural and electronic properties of interfaces between fluorographane and MoS2. Unsymmetrical functionalization of graphene with H and F results in an intrinsic dipole moment perpendicular to the plane of the buckled graphene skeleton. Depending on the orientation of this dipole moment, the electronic properties of a physically absorbed MoS2 monolayer can be switched from n-to p-type or vice versa. We show that one can realize vanishing n-type/p-type Schottky barrier heights when contacting MoS2 to fluorographane. By applying a perpendicular electric field, the size of the Schottky barrier and the degree of doping can be tuned. Our calculations indicate that a fluorographane monolayer is a promising candidate for bipolar doping of MoS2, which is vital in the design of novel technological applications based on two-dimensional materials.
Address
Corporate Author Thesis
Publisher Place of Publication Cambridge Editor
Language Wos 000363193800043 Publication Date 2015-09-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1463-9076 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.123 Times cited 7 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TRGrid e-Infrastructure), and HPC infrastructure of the University of Antwerp (CalcUA) a division of the Flemish Supercomputer Center (VSC), which is funded by the Hercules foundation. ; Approved (up) Most recent IF: 4.123; 2015 IF: 4.493
Call Number UA @ lucian @ c:irua:129477 Serial 4182
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Author Kang, J.; Sahin, H.; Peeters, F.M.
Title Mechanical properties of monolayer sulphides : a comparative study between MoS2, HfS2 and TiS3 Type A1 Journal article
Year 2015 Publication Physical chemistry, chemical physics Abbreviated Journal Phys Chem Chem Phys
Volume 17 Issue 17 Pages 27742-27749
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract The in-plane stiffness (C), Poisson's ratio (nu), Young's modulus and ultimate strength (sigma) along two different crystallographic orientations are calculated for the single layer crystals: MoS2, HfS2 and TiS3 in 1H, 1T and monoclinic phases. We find that MoS2 and HfS2 have isotropic in-plane stiffnesses of 124.24 N m(-1) and 79.86 N m(-1), respectively. While for TiS3 the in-plane stiffness is highly anisotropic due to its monoclinic structure, with C-x = 83.33 N m(-1) and C-y = 133.56 N m(-1) (x and y are parallel to its longer and shorter in-plane lattice vectors.). HfS2 which is in the 1T phase has the smallest anisotropy in its ultimate strength, whereas TiS3 in the monoclinic phase has the largest. Along the armchair direction MoS2 has the largest sigma of 23.48 GPa, whereas along y TiS3 has the largest sigma of 18.32 GPa. We have further analyzed the band gap response of these materials under uniaxial tensile strain, and find that they exhibit different behavior. Along both armchair and zigzag directions, the band gap of MoS2 (HfS2) decreases (increases) as strain increases, and the response is almost isotropic. For TiS3, the band gap decreases when strain is along x, while if strain is along y, the band gap increases first and then decreases beyond a threshold strain value. The different characteristics observed in these sulphides with different structures shed light on the relationship between the structure and properties, which is useful for applications in nanotechnology.
Address
Corporate Author Thesis
Publisher Place of Publication Cambridge Editor
Language Wos 000363193800055 Publication Date 2015-09-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1463-9076 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.123 Times cited 83 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure), and HPC infrastructure of the University of Antwerp (CalcUA) a division of the Flemish Super-computer Center (VSC), which is funded by the Hercules foundation. H.S. is supported by a FWO Pegasus-Long Marie Curie Fellowship, and J.K. by a FWO Pegasus-Short Marie Curie Fellowship. ; Approved (up) Most recent IF: 4.123; 2015 IF: 4.493
Call Number UA @ lucian @ c:irua:129478 Serial 4204
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Author Bafekry, A.; Stampfl, C.; Shayesteh, S.F.; Peeters, F.M.
Title Exploiting the novel electronic and magnetic structure of C3Nvia functionalization and conformation Type A1 Journal article
Year 2019 Publication Advanced Electronic Materials Abbreviated Journal Adv Electron Mater
Volume 5 Issue 5 Pages 1900459
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract 2D polyaniline, C3N, is of recent high interest due to its unusual properties and potential use in various technological applications. In this work, through systematic first-principles calculations, the atomic, electronic, and magnetic structure of C3N and the changes induced due to functionalization by the adsorption of hydrogen, oxygen, and fluorine, for different coverages and sites, as well as on formation of nanoribbons including the effect of adsorbed hydrogen and oxygen, and the effect of strain, are investigated. Among other interesting phenomena, for hydrogen adsorption, a semiconductor-to-topological insulator transition, where two Dirac-points appear around the Fermi level, as well as ferromagnetic ordering for both hydrogen and oxygen functionalization, is identified. Considering C3N nanoribbons, adsorption of H leads to significant changes in the electronic properties, such as transforming the structures from semiconductor to metallic. Furthermore, investigating the effect of strain on the physical properties, it is found that the band gap can be significantly altered and controlled. The present findings predict that a wide variation in the magnetic and electronic structure of C3N can be achieved by adatom functionalization and conformation indicating its high potential for use in various technological applications, ranging from catalysis, energy storage, and nanoelectronic devices.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000486528200001 Publication Date 2019-09-13
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2199-160x ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.193 Times cited 39 Open Access
Notes ; This work was supported by the FLAG-ERA project 2DTRANS and the Flemish Science Foundation (FWO-Vl). In addition, we acknowledge the OpenMX team for OpenMX code. ; Approved (up) Most recent IF: 4.193
Call Number UA @ admin @ c:irua:162790 Serial 5414
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Author Xiao, H.; Zhang, Z.; Xu, W.; Wang, Q.; Xiao, Y.; Ding, L.; Huang, J.; Li, H.; He, B.; Peeters, F.M.
Title Terahertz optoelectronic properties of synthetic single crystal diamond Type A1 Journal article
Year 2023 Publication Diamond and related materials Abbreviated Journal
Volume 139 Issue Pages 110266-110268
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract A systematic investigation is undertaken for studying the optoelectronic properties of single crystal diamond (SCD) grown by microwave plasma chemical vapor deposition (MPCVD). It is indicated that, without intentional doping and surface treatment during the sample growth, the terahertz (THz) optical conduction in SCD is mainly affected by surface H-terminations, -OH-, O- and N-based functional groups. By using THz time-domain spectroscopy (TDS), we measure the transmittance, the complex dielectric constant and optical conductivity σ(ω) of SCD. We find that SCD does not show typical semiconductor characteristics in THz regime, where σ(ω) cannot be described rightly by the conventional Drude formula. Via fitting the real and imaginary parts of σ(ω) to the Drude-Smith formula, the ratio of the average carrier density to the effective electron mass γ = ne/m*, the electronic relaxation time τ and the electronic backscattering or localization factor can be determined optically. The temperature dependence of these parameters is examined. From the temperature dependence of γ, a metallic to semiconductor transition is observed at about T = 10 K. The temperature dependence of τ is mainly induced by electron coupling with acoustic-phonons and there is a significant effect of photon-induced electron backscattering or localization in SCD. This work demonstrates that THz TDS is a powerful technique in studying SCD which contains H-, N- and O-based bonds and has low electron density and high dc resistivity. The results obtained from this study can benefit us to gain an in-depth understanding of SCD and may provide new guidance for the application of SCD as electronic, optical and optoelectronic materials.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date 2023-08-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0925-9635 ISBN Additional Links UA library record
Impact Factor 4.1 Times cited Open Access
Notes Approved (up) Most recent IF: 4.1; 2023 IF: 2.561
Call Number UA @ admin @ c:irua:200920 Serial 9103
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Author Sarmadian, N.; Saniz, R.; Partoens, B.; Lamoen, D.
Title Easily doped p-type, low hole effective mass, transparent oxides Type A1 Journal article
Year 2016 Publication Scientific reports Abbreviated Journal Sci Rep-Uk
Volume 6 Issue 6 Pages 20446
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
Abstract Fulfillment of the promise of transparent electronics has been hindered until now largely by the lack of semiconductors that can be doped p-type in a stable way, and that at the same time present high hole mobility and are highly transparent in the visible spectrum. Here, a high-throughput study based on first-principles methods reveals four oxides, namely X2SeO2, with X = La, Pr, Nd, and Gd, which are unique in that they exhibit excellent characteristics for transparent electronic device applications – i.e., a direct band gap larger than 3.1 eV, an average hole effective mass below the electron rest mass, and good p-type dopability. Furthermore, for La2SeO2 it is explicitly shown that Na impurities substituting La are shallow acceptors in moderate to strong anion-rich growth conditions, with low formation energy, and that they will not be compensated by anion vacancies VO or VSe.
Address EMAT, Departement Fysica, Universiteit Antwerpen, Groenenborgerlaan 171, B-2020 Antwerpen, Belgium
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Wos 000369568900001 Publication Date 2016-02-08
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 55 Open Access
Notes We acknowledge the financial support of FWO-Vlaanderen through project G.0150.13 and of a GOA fund from the University of Antwerp. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the Hercules Foundation and the Flemish Government–department EWI. Approved (up) Most recent IF: 4.259
Call Number c:irua:131611 Serial 4036
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Author Zarenia, M.; Perali, A.; Peeters, F.M.; Neilson, D.
Title Large gap electron-hole superfluidity and shape resonances in coupled graphene nanoribbons Type A1 Journal article
Year 2016 Publication Scientific reports Abbreviated Journal Sci Rep-Uk
Volume 6 Issue 6 Pages 24860
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract We predict enhanced electron-hole superfluidity in two coupled electron-hole armchair-edge terminated graphene nanoribbons separated by a thin insulating barrier. In contrast to graphene monolayers, the multiple subbands of the nanoribbons are parabolic at low energy with a gap between the conduction and valence bands, and with lifted valley degeneracy. These properties make screening of the electron-hole interaction much weaker than for coupled electron-hole monolayers, thus boosting the pairing strength and enhancing the superfluid properties. The pairing strength is further boosted by the quasi one-dimensional quantum confinement of the carriers, as well as by the large density of states near the bottom of each subband. The latter magnifies superfluid shape resonances caused by the quantum confinement. Several superfluid partial condensates are present for finite-width nanoribbons with multiple subbands. We find that superfluidity is predominately in the strongly-coupled BEC and BCS-BEC crossover regimes, with large superfluid gaps up to 100 meV and beyond. When the gaps exceed the subband spacing, there is significant mixing of the subbands, a rounding of the shape resonances, and a resulting reduction in the one-dimensional nature of the system.
Address
Corporate Author Thesis
Publisher Nature Publishing Group Place of Publication London Editor
Language Wos 000374654500002 Publication Date 2016-04-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2045-2322 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.259 Times cited 7 Open Access
Notes ; M.Z. acknowledges support by the Flemish Science Foundation (FWO-Vl), the University Research Fund (BOF), and the European Science Foundation (POLATOM). A.P. and D.N. acknowledge support by the University of Camerino FAR project CESEMN. The authors thank the colleagues involved in the MultiSuper International Network (http://www.multisuper.org) for exchange of ideas and suggestions for this work. ; Approved (up) Most recent IF: 4.259
Call Number UA @ lucian @ c:irua:133619 Serial 4201
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Author Schouteden, K.; Li, Z.; Chen, T.; Song, F.; Partoens, B.; Van Haesendonck, C.; Park, K.
Title Moire superlattices at the topological insulator Bi2Te3 Type A1 Journal article
Year 2016 Publication Scientific reports Abbreviated Journal Sci Rep-Uk
Volume 6 Issue 6 Pages 20278
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract We report on the observation of complex superlattices at the surface of the topological insulator Bi2Te3. Scanning tunneling microscopy reveals the existence of two different periodic structures in addition to the Bi2Te3 atomic lattice, which is found to strongly affect the local electronic structure. These three different periodicities are interpreted to result from a single small in-plane rotation of the topmost quintuple layer only. Density functional theory calculations support the observed increase in the DOS near the Fermi level, and exclude the possibility that strain is at the origin of the observed Moire pattern. Exploration of Moire superlattices formed by the quintuple layers of topological insulators holds great potential for further tuning of the properties of topological insulators.
Address
Corporate Author Thesis
Publisher Nature Publishing Group Place of Publication London Editor
Language Wos 000369543200001 Publication Date 2016-02-08
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 14 Open Access
Notes ; The research in Leuven and Antwerp has been supported by the Research Foundation – Flanders (FWO, Belgium). The research in Leuven received additional support from the Flemish Concerted Research Action program (BOF KU Leuven, Project No. GOA/14/007). Z.L. thanks the China Scholarship Council for financial support (No. 2011624021). K.S. acknowledges support from the FWO. K.P. was supported by U.S. National Science Foundation DMR-1206354 and San Diego Supercomputer Center (SDSC) Trestles under DMR060009N. T.C. and F.S. acknowledge the financial support of the National Key Projects for Basic Research of China (Grant Nos: 2013CB922103), the National Natural Science Foundation of China (Grant Nos: 91421109, 11522432), the PAPD project, and the Natural Science Foundation of Jiangsu Province (Grant BK20130054). ; Approved (up) Most recent IF: 4.259
Call Number UA @ lucian @ c:irua:131612 Serial 4208
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Author Suslu, A.; Wu, K.; Sahin, H.; Chen, B.; Yang, S.; Cai, H.; Aoki, T.; Horzum, S.; Kang, J.; Peeters, F.M.; Tongay, S.;
Title Unusual dimensionality effects and surface charge density in 2D Mg(OH)2 Type A1 Journal article
Year 2016 Publication Scientific reports Abbreviated Journal Sci Rep-Uk
Volume 6 Issue 6 Pages 20525
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract We present two-dimensional Mg(OH)(2) sheets and their vertical heterojunctions with CVD-MoS2 for the first time as flexible 2D insulators with anomalous lattice vibration and chemical and physical properties. New hydrothermal crystal growth technique enabled isolation of environmentally stable monolayer Mg(OH)(2) sheets. Raman spectroscopy and vibrational calculations reveal that the lattice vibrations of Mg(OH)(2) have fundamentally different signature peaks and dimensionality effects compared to other 2D material systems known to date. Sub-wavelength electron energy-loss spectroscopy measurements and theoretical calculations show that Mg(OH)(2) is a 6 eV direct-gap insulator in 2D, and its optical band gap displays strong band renormalization effects from monolayer to bulk, marking the first experimental confirmation of confinement effects in 2D insulators. Interestingly, 2D-Mg(OH)(2) sheets possess rather strong surface polarization (charge) effects which is in contrast to electrically neutral h-BN materials. Using 2D-Mg(OH)(2) sheets together with CVD-MoS2 in the vertical stacking shows that a strong change transfer occurs from n-doped CVD-MoS2 sheets to Mg(OH)(2), naturally depleting the semiconductor, pushing towards intrinsic doping limit and enhancing overall optical performance of 2D semiconductors. Results not only establish unusual confinement effects in 2D-Mg(OH)(2), but also offer novel 2D-insulating material with unique physical, vibrational, and chemical properties for potential applications in flexible optoelectronics.
Address
Corporate Author Thesis
Publisher Nature Publishing Group Place of Publication London Editor
Language Wos 000369510300001 Publication Date 2016-02-05
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 39 Open Access
Notes ; This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem foundation of the Flemish government. Computational resources were provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e-Infrastructure). HS is supported by a FWO Pegasus Long Marie Curie Fellowship. JK is supported by a FWO Pegasus-short Marie Curie Fellowship. We acknowledge the use of John M. Cowley Center for High Resolution Electron Microscopy at Arizona State University. ; Approved (up) Most recent IF: 4.259
Call Number UA @ lucian @ c:irua:131615 Serial 4272
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Author Jelić, Z.L.; Milošević, M.V.; Silhanek, A.V.
Title Velocimetry of superconducting vortices based on stroboscopic resonances Type A1 Journal article
Year 2016 Publication Scientific reports Abbreviated Journal Sci Rep-Uk
Volume 6 Issue Pages 35687
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract An experimental determination of the mean vortex velocity in superconductors mostly relies on the measurement of flux-flow resistance with magnetic field, temperature, or driving current. In the present work we introduce a method combining conventional transport measurements and a frequency-tuned flashing pinning potential to obtain reliable estimates of the vortex velocity. The proposed device is characterized using the time-dependent Ginzburg-Landau formalism, where the velocimetry method exploits the resonances in mean vortex dissipation when temporal commensuration occurs between the vortex crossings and the flashing potential. We discuss the sensitivity of the proposed technique on applied current, temperature and heat diffusion, as well as the vortex core deformations during fast motion.
Address
Corporate Author Thesis
Publisher Nature Publishing Group Place of Publication London Editor
Language Wos 000385919600001 Publication Date 2016-10-24
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 22 Open Access
Notes ; This work was supported by the Research Foundation-Flanders (FWO) and EU COST action MP1201. The work of Z.L.J. and A.V.S. was partially supported by “Mandat d'Impulsion Scientifique” MIS F.4527.13 of the F.R.S.-FNRS. ; Approved (up) Most recent IF: 4.259
Call Number UA @ lucian @ c:irua:144636 Serial 4701
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Author Zarenia, M.; Neilson, D.; Peeters, F.M.
Title Inhomogeneous phases in coupled electron-hole bilayer graphene sheets : charge density waves and coupled wigner crystals Type A1 Journal article
Year 2017 Publication Scientific reports Abbreviated Journal Sci Rep-Uk
Volume 7 Issue Pages 11510
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Recently proposed accurate correlation energies are used to determine the phase diagram of strongly coupled electron-hole graphene bilayers. The control parameters of the phase diagram are the charge carrier density and the insulating barrier thickness separating the bilayers. In addition to the electron-hole superfluid phase we find two new inhomogeneous ground states, a one dimensional charge density wave phase and a coupled electron-hole Wigner crystal. The elementary crystal structure of bilayer graphene plays no role in generating these new quantum phases, which are completely determined by the electrons and holes interacting through the Coulomb interaction. The experimental parameters for the new phases lie within attainable ranges and therefore coupled electron-hole bilayer graphene presents itself as an experimental system where novel emergent many-body phases can be realized.
Address
Corporate Author Thesis
Publisher Nature Publishing Group Place of Publication London Editor
Language Wos 000410739000008 Publication Date 2017-09-11
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 13 Open Access
Notes ; We thank Alex Hamilton, Bart Partoens, and Andrea Perali for useful discussions. This work was partially supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem program of the Flemish government. D.N. acknowledges support by the University of Camerino FAR project CESEMN. ; Approved (up) Most recent IF: 4.259
Call Number UA @ lucian @ c:irua:145620 Serial 4742
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Author Zografos, O.; Manfrini, M.; Vaysset, A.; Sorée, B.; Ciubotaru, F.; Adelmann, C.; Lauwereins, R.; Raghavan, P.; Radu, I.P.
Title Exchange-driven magnetic logic Type A1 Journal article
Year 2017 Publication Scientific reports Abbreviated Journal Sci Rep-Uk
Volume 7 Issue Pages 12154
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract Direct exchange interaction allows spins to be magnetically ordered. Additionally, it can be an efficient manipulation pathway for low-powered spintronic logic devices. We present a novel logic scheme driven by exchange between two distinct regions in a composite magnetic layer containing a bistable canted magnetization configuration. By applying a magnetic field pulse to the input region, the magnetization state is propagated to the output via spin-to-spin interaction in which the output state is given by the magnetization orientation of the output region. The dependence of this scheme with input field conditions is extensively studied through a wide range of micromagnetic simulations. These results allow different logic operating modes to be extracted from the simulation results, and majority logic is successfully demonstrated.
Address
Corporate Author Thesis
Publisher Nature Publishing Group Place of Publication London Editor
Language Wos 000411434900020 Publication Date 2017-09-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2045-2322 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 4.259 Times cited 7 Open Access
Notes ; ; Approved (up) Most recent IF: 4.259
Call Number UA @ lucian @ c:irua:146742 Serial 4784
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Author Berdiyorov, G.R.; Milošević, M.V.; Hernandez-Nieves, A.D.; Peeters, F.M.; Dominguez, D.
Title Microfluidic manipulation of magnetic flux domains in type-I superconductors : droplet formation, fusion and fission Type A1 Journal article
Year 2017 Publication Scientific reports Abbreviated Journal Sci Rep-Uk
Volume 7 Issue Pages 12129
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract The magnetic flux domains in the intermediate state of type-I superconductors are known to resemble fluid droplets, and their dynamics in applied electric current is often cartooned as a “dripping faucet”. Here we show, using the time-depended Ginzburg-Landau simulations, that microfluidic principles hold also for the determination of the size of the magnetic flux-droplet as a function of the applied current, as well as for the merger or splitting of those droplets in the presence of the nanoengineered obstacles for droplet motion. Differently from fluids, the flux-droplets in superconductors are quantized and dissipative objects, and their pinning/depinning, nucleation, and splitting occur in a discretized form, all traceable in the voltage measured across the sample. At larger applied currents, we demonstrate how obstacles can cause branching of laminar flux streams or their transformation into mobile droplets, as readily observed in experiments.
Address
Corporate Author Thesis
Publisher Nature Publishing Group Place of Publication London Editor
Language Wos 000411416700032 Publication Date 2017-09-15
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 1 Open Access
Notes ; This work was supported by the Research Foundation Flanders (FWO) and the MINCYT-FWO FW/14/04 bilateral project. A.D.H. and D.D. acknowledge support from CONICET (Grant No. PIP111220150100218), CNEA and ANPCyT (Grant No. PICT2014-1382). ; Approved (up) Most recent IF: 4.259
Call Number UA @ lucian @ c:irua:146743 Serial 4789
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Author de Aquino, B.R.H.; Neek-Amal, M.; Milošević, M.V.
Title Unconventional two-dimensional vibrations of a decorated carbon nanotube under electric field : linking actuation to advanced sensing ability Type A1 Journal article
Year 2017 Publication Scientific reports Abbreviated Journal Sci Rep-Uk
Volume 7 Issue Pages 13481
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract We show that a carbon nanotube decorated with different types of charged metallic nanoparticles exhibits unusual two-dimensional vibrations when actuated by applied electric field. Such vibrations and diverse possible trajectories are not only fundamentally important but also have minimum two characteristic frequencies that can be directly linked back to the properties of the constituents in the considered nanoresonator. Namely, those frequencies and the maximal deflection during vibrations are very distinctively dependent on the geometry of the nanotube, the shape, element, mass and charge of the nanoparticle, and are vastly tunable by the applied electric field, revealing the unique sensing ability of devices made of molecular filaments and metallic nanoparticles.
Address
Corporate Author Thesis
Publisher Nature Publishing Group Place of Publication London Editor
Language Wos 000413188600005 Publication Date 2017-10-12
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 1 Open Access
Notes ; This work was supported by the Research Foundation – Flanders (FWO) and Shahid Rajaee Teacher Training University. ; Approved (up) Most recent IF: 4.259
Call Number UA @ lucian @ c:irua:146672 Serial 4796
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