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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 pdf  url
doi  openurl
  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 (up) 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  
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Author Wang, H.; Su, L.; Yagmurcukardes, M.; Chen, J.; Jiang, Y.; Li, Z.; Quan, A.; Peeters, F.M.; Wang, C.; Geim, A.K.; Hu, S. pdf  doi
openurl 
  Title Blue energy conversion from holey-graphene-like membranes with a high density of subnanometer pores Type A1 Journal article
  Year 2020 Publication Nano Letters Abbreviated Journal Nano Lett  
  Volume 20 Issue 12 Pages 8634-8639  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Blue energy converts the chemical potential difference from salinity gradients into electricity via reverse electrodialysis and provides a renewable source of clean energy. To achieve high energy conversion efficiency and power density, nanoporous membrane materials with both high ionic conductivity and ion selectivity are required. Here, we report ion transport through a network of holey-graphene-like sheets made by bottom-up polymerization. The resulting ultrathin membranes provide controlled pores of <10 angstrom in diameter with an estimated density of about 10(12) cm(-2). The pores' interior contains NH2 groups that become electrically charged with varying pH and allow tunable ion selectivity. Using the holey-graphene-like membranes, we demonstrate power outputs reaching hundreds of watts per square meter. The work shows a viable route toward creating membranes with high-density angstrom-scale pores, which can be used for energy generation, ion separation, and related technologies.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000599507100032 Publication Date 2020-11-12  
  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 (up) 10.8 Times cited 29 Open Access  
  Notes ; The authors acknowledge supported from National Key Research and Development Program of China (2019YFA0705400, 2018YFA0209500), and National Natural Science Foundation of China (21972121, 21671162). M. Y. acknowledges the Flemish Science Foundation (FWO-Vl) postdoctoral fellowship. ; Approved Most recent IF: 10.8; 2020 IF: 12.712  
  Call Number UA @ admin @ c:irua:175048 Serial 6685  
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Author Achari, A.; Bekaert, J.; Sreepal, V.; Orekhov, A.; Kumaravadivel, P.; Kim, M.; Gauquelin, N.; Pillai, P.B.; Verbeeck, J.; Peeters, F.M.; Geim, A.K.; Milošević, M.V.; Nair, R.R. url  doi
openurl 
  Title Alternating superconducting and charge density wave monolayers within bulk 6R-TaS₂ Type A1 Journal article
  Year 2022 Publication Nano letters Abbreviated Journal Nano Lett  
  Volume 22 Issue 15 Pages 6268-6275  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)  
  Abstract Van der Waals (vdW) heterostructures continue to attract intense interest as a route of designing materials with novel properties that cannot be found in nature. Unfortunately, this approach is currently limited to only a few layers that can be stacked on top of each other. Here, we report a bulk vdW material consisting of superconducting 1H TaS2 monolayers interlayered with 1T TaS2 monolayers displaying charge density waves (CDW). This bulk vdW heterostructure is created by phase transition of 1T-TaS2 to 6R at 800 degrees C in an inert atmosphere. Its superconducting transition (T-c) is found at 2.6 K, exceeding the T-c of the bulk 2H phase. Using first-principles calculations, we argue that the coexistence of superconductivity and CDW within 6R-TaS2 stems from amalgamation of the properties of adjacent 1H and 1T monolayers, where the former dominates the superconducting state and the latter the CDW behavior.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000831832100001 Publication Date 2022-07-20  
  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 (up) 10.8 Times cited 8 Open Access OpenAccess  
  Notes This work was supported by the Royal Society, the Leverhulme Trust (PLP-2018-220), the Engineering and Physical Sciences Research Council (EP/N005082/1), and European Research Council (contract 679689). The authors acknowledge the use of the facilities at the Henry Royce Institute and associated support services. J.B. is a postdoctoral fellow of Research Foundation-Flanders (FWO-Vlaanderen). Computational resources were provided by the VSC (Flemish Supercomputer Center), funded by the FWO and the Flemish Governmentdepartment EWI. This work was also performed under a transnational access provision funded by the European Union under the Horizon 2020 programme within a contract for Integrating Activities for Advanced Communities No 823717 − ESTEEM3; esteem3reported; esteem3jra Approved Most recent IF: 10.8  
  Call Number UA @ admin @ c:irua:189495 Serial 7077  
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Author Gobato, Y.G.; de Brito, C.S.; Chaves, A.; Prosnikov, M.A.; Wozniak, T.; Guo, S.; Barcelos, I.D.; Milošević, M.V.; Withers, F.; Christianen, P.C.M. pdf  url
doi  openurl
  Title Distinctive g-factor of Moire-confined excitons in van der Waals heterostructures Type A1 Journal article
  Year 2022 Publication Nano letters Abbreviated Journal Nano Lett  
  Volume 22 Issue 21 Pages 8641-8641  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract We investigated the valley Zeeman splitting of excitonic peaks in the microphotoluminescence (mu PL) spectra of high-quality hBN/WS2/MoSe2/hBN heterostructures under perpendicular magnetic fields up to 20 T. We identify two neutral exciton peaks in the mu PL spectra; the lower-energy peak exhibits a reduced g-factor relative to that of the higher energy peak and much lower than the recently reported values for interlayer excitons in other van der Waals (vdW) heterostructures. We provide evidence that such a discernible g-factor stems from the spatial confinement of the exciton in the potential landscape created by the moire pattern due to lattice mismatch or interlayer twist in heterobilayers. This renders magneto-mu PL an important tool to reach a deeper understanding of the effect of moire patterns on excitonic confinement in vdW heterostructures.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000877287800001 Publication Date 2022-10-24  
  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 (up) 10.8 Times cited 3 Open Access OpenAccess  
  Notes Approved Most recent IF: 10.8  
  Call Number UA @ admin @ c:irua:192166 Serial 7298  
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Author Cai, J.; Griffin, E.; Guarochico-Moreira, V.; Barry, D.; Xin, B.; Huang, S.; Geim, A.K.; Peeters, F.M.; Lozada-Hidalgo, M. url  doi
openurl 
  Title Photoaccelerated water dissociation across one-atom-thick electrodes Type A1 Journal article
  Year 2022 Publication Nano letters Abbreviated Journal Nano Lett  
  Volume 22 Issue 23 Pages 9566-9570  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Recent experiments demonstrated that interfacial water dissociation (H2O ⇆ H+ + OH-) could be accelerated exponentially by an electric field applied to graphene electrodes, a phenomenon related to the Wien effect. Here we report an order-of-magnitude acceleration of the interfacial water dissociation reaction under visible-light illumination. This process is accompanied by spatial separation of protons and hydroxide ions across one-atom-thick graphene and enhanced by strong interfacial electric fields. The found photoeffect is attributed to the combination of graphene's perfect selectivity with respect to protons, which prevents proton-hydroxide recombination, and to proton transport acceleration by the Wien effect, which occurs in synchrony with the water dissociation reaction. Our findings provide fundamental insights into ion dynamics near atomically thin proton-selective interfaces and suggest that strong interfacial fields can enhance and tune very fast ionic processes, which is of relevance for applications in photocatalysis and designing reconfigurable materials.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000892112200001 Publication Date 2022-11-30  
  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 (up) 10.8 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 10.8  
  Call Number UA @ admin @ c:irua:192759 Serial 7330  
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Author Torun, E.; Paleari, F.; Milošević, M.V.; Wirtz, L.; Sevik, C. pdf  url
doi  openurl
  Title Intrinsic control of interlayer exciton generation in Van der Waals materials via Janus layers Type A1 Journal article
  Year 2023 Publication Nano letters Abbreviated Journal  
  Volume 23 Issue 8 Pages 3159-3166  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract We demonstrate the possibility of engineering the optical properties of transition metal dichalcogenide heterobilayers when one of the constitutive layers has a Janus structure. We investigate different MoS2@Janus layer combinations using first-principles methods including excitons and exciton-phonon coupling. The direction of the intrinsic electric field from the Janus layer modifies the electronic band alignments and, consequently, the energy separation between dark interlayer exciton states and bright in-plane excitons. We find that in-plane lattice vibrations strongly couple the two states, so that exciton-phonon scattering may be a viable generation mechanism for interlayer excitons upon light absorption. In particular, in the case of MoS2@WSSe, the energy separation of the low-lying interlayer exciton from the in-plane exciton is resonant with the transverse optical phonon modes (40 meV). We thus identify this heterobilayer as a prime candidate for efficient generation of charge-separated electron-hole pairs.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000969732100001 Publication Date 2023-04-10  
  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 (up) 10.8 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 10.8; 2023 IF: 12.712  
  Call Number UA @ admin @ c:irua:196034 Serial 8118  
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Author Bafekry, A.; Stampfl, C.; Ghergherehchi, M.; Shayesteh, S.F. pdf  url
doi  openurl
  Title A first-principles study of the effects of atom impurities, defects, strain, electric field and layer thickness on the electronic and magnetic properties of the C2N nanosheet Type A1 Journal article
  Year 2020 Publication Carbon Abbreviated Journal Carbon  
  Volume 157 Issue 157 Pages 371-384  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Using the first-principles calculations, we explore the structural and novel electronic/optical properties of the C2N nanosheet. To this goal, we systematically investigate the affect of layer thickness, electrical field and strain on the electronic properties of the C2N nanosheet. By increasing the thickness of C2N, we observed that the band gap decreases. Moreover, by applying an electrical field to bilayer C2N, the band gap decreases and a semiconductor-to-metal transition can occur. Our results also confirm that uniaxial and biaxial strain can effectively alter the band gap of C2N monolayer. Furthermore, we show that the electronic and magnetic properties of C2N can be modified by the adsorption and substitution of various atoms. Depending on the species of embedded atoms, they may induce semiconductor (O, C, Si and Be), metal (S, N, P, Na, K, Mg and Ca), dilute-magnetic semiconductor (H, F, B), or ferro-magnetic-metal (Cl, Li) character in C2N monolayer. It was also found that the inclusion of hydrogen or oxygen impurities and nitrogen vacancies, can induce magnetism in the C2N monolayer. These extensive calculations can be useful to guide future studies to modify the electronic/optical properties of two-dimensional materials. (C) 2019 Elsevier Ltd. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000502548500044 Publication Date 2019-10-22  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0008-6223 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 10.9 Times cited 49 Open Access  
  Notes ; This work was supported by the National Research Foundation of Korea grant funded by the Korea government (MSIT) (NRF-2017R1A2B2011989). We are thankful for comments by Meysam Baghery Tagani from department of physics in University of Guilan and Bohayra Mortazavi from Gottfried Wilhelm Leibniz Universitat Hannover, Hannover, Germany. ; Approved Most recent IF: 10.9; 2020 IF: 6.337  
  Call Number UA @ admin @ c:irua:165024 Serial 6283  
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Author Bafekry, A.; Yagmurcukardes, M.; Shahrokhi, M.; Ghergherehchi, M. pdf  doi
openurl 
  Title Electro-optical properties of monolayer and bilayer boron-doped C₃N: Tunable electronic structure via strain engineering and electric field Type A1 Journal article
  Year 2020 Publication Carbon Abbreviated Journal Carbon  
  Volume 168 Issue Pages 220-229  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract In this work, the structural, electronic and optical properties of monolayer and bilayer of boron doped C3N are investigated by means of density functional theory-based first-principles calculations. Our results show that with increasing the B dopant concentration from 3.1% to 12.5% in the hexagonal pattern, an indirect-to-direct band gap (0.8 eV) transition occurs. Furthermore, we study the effect of electric field and strain on the B doped C3N bilayer (B-C3N@2L). It is shown that by increasing E-field strength from 0.1 to 0.6V/angstrom, the band gap displays almost a linear decreasing trend, while for the > 0.6V/angstrom, we find dual narrow band gap with of 50 meV (in parallel E-field) and 0.4 eV (in antiparallel E-field). Our results reveal that in-plane and out-of-plane strains can modulate the band gap and band edge positions of the B-C3N@2L. Overall, we predict that B-C3N@2L is a new platform for the study of novel physical properties in layered two-dimensional materials (2DM) which may provide new opportunities to realize high-speed low-dissipation devices. (C) 2020 Elsevier Ltd. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000565900900008 Publication Date 2020-07-13  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0008-6223 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 10.9 Times cited 21 Open Access  
  Notes ; This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government(MSIT) (NRF-2017R1A2B2011989). M. Yagmurcukardes acknowledges Flemish Science Foundation (FWO-VI) by a postdoctoral fellowship. ; Approved Most recent IF: 10.9; 2020 IF: 6.337  
  Call Number UA @ admin @ c:irua:171914 Serial 6500  
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Author Chen, X.; Bouhon, A.; Li, L.; Peeters, F.M.; Sanyal, B. url  doi
openurl 
  Title PAI-graphene : a new topological semimetallic two-dimensional carbon allotrope with highly tunable anisotropic Dirac cones Type A1 Journal article
  Year 2020 Publication Carbon Abbreviated Journal Carbon  
  Volume 170 Issue Pages 477-486  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Using evolutionary algorithm for crystal structure prediction, we present a new stable two-dimensional (2D) carbon allotrope composed of polymerized as-indacenes (PAI) in a zigzag pattern, namely PAI-graphene whose energy is lower than most of the reported 2D allotropes of graphene. Crucially, the crystal structure realizes a nonsymmorphic layer group that enforces a nontrivial global topology of the band structure with two Dirac cones lying perfectly at the Fermi level. The absence of electron/hole pockets makes PAI-graphene a pristine crystalline topological semimetal having anisotropic Fermi velocities with a high value of 7.0 x 10(5) m/s. We show that while the semimetallic property of the allotrope is robust against the application of strain, the positions of the Dirac cone and the Fermi velocities can be modified significantly with strain. Moreover, by combining strain along both the x- and y-directions, two band inversions take place at G leading to the annihilation of the Dirac nodes demonstrating the possibility of strain-controlled conversion of a topological semimetal into a semiconductor. Finally we formulate the bulk-boundary correspondence of the topological nodal phase in the form of a generalized Zak-phase argument finding a perfect agreement with the topological edge states computed for different edge-terminations. (C) 2020 The Author(s). Published by Elsevier Ltd.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000579779800047 Publication Date 2020-08-21  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0008-6223 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 10.9 Times cited 27 Open Access  
  Notes ; We thank S. Nahas, for helpful discussions. This work is supported by the project grant (2016e05366) and Swedish Research Links program grant (2017e05447) from the Swedish Research Council, the Fonds voor Wetenschappelijk Onderzoek (FWO-Vl), the FLAG-ERA project TRANS 2D TMD. Linyang Li acknowledges financial support from the Natural Science Foundation of Hebei Province (Grant No. A2020202031). X.C. thanks China scholarship council for financial support (No. 201606220031). X.C. and B.S. acknowledge SNIC-UPPMAX, SNIC-HPC2N, and SNIC-NSC centers under the Swedish National Infrastructure for Computing (SNIC) resources for the allocation of time in high-performance supercomputers. Moreover, supercomputing resources from PRACE DECI-15 project DYNAMAT are gratefully acknowledged. ; Approved Most recent IF: 10.9; 2020 IF: 6.337  
  Call Number UA @ admin @ c:irua:173513 Serial 6577  
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Author Mirzakhani, M.; Myoung, N.; Peeters, F.M.; Park, H.C. pdf  doi
openurl 
  Title Electronic Mach-Zehnder interference in a bipolar hybrid monolayer-bilayer graphene junction Type A1 Journal article
  Year 2023 Publication Carbon Abbreviated Journal  
  Volume 201 Issue Pages 734-744  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract Graphene matter in a strong magnetic field, realizing one-dimensional quantum Hall channels, provides a unique platform for studying electron interference. Here, using the Landauer-Buttiker formalism along with the tightbinding model, we investigate the quantum Hall (QH) effects in unipolar and bipolar monolayer-bilayer graphene (MLG-BLG) junctions. We find that a Hall bar made of an armchair MLG-BLG junction in the bipolar regime results in valley-polarized edgechannel interferences and can operate a fully tunable Mach-Zehnder (MZ) interferometer device. Investigation of the bar-width and magnetic-field dependence of the conductance oscillations shows that the MZ interference in such structures can be drastically affected by the type of (zigzag) edge termination of the second layer in the BLG region [composed of vertical dimer or non-dimer atoms]. Our findings reveal that both interfaces exhibit a double set of Aharonov-Bohm interferences, with the one between two oppositely valley-polarized edge channels dominating and causing a large amplitude conductance oscillation ranging from 0 to 2e2/h. We explain and analyze our findings by analytically solving the Dirac-Weyl equation for a gated semi-infinite MLG-BLG junction.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000868911500004 Publication Date 2022-09-28  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0008-6223 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 10.9 Times cited Open Access Not_Open_Access  
  Notes Approved Most recent IF: 10.9; 2023 IF: 6.337  
  Call Number UA @ admin @ c:irua:191516 Serial 7302  
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Author Pandey, T.; Du, M.-H.; Parker, D.S.; Lindsay, L. pdf  doi
openurl 
  Title Origin of ultralow phonon transport and strong anharmonicity in lead-free halide perovskites Type A1 Journal article
  Year 2022 Publication Materials Today Physics Abbreviated Journal  
  Volume 28 Issue Pages 100881-10  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract All-inorganic lead-free halide double perovskites offer a promising avenue toward non-toxic, stable optoelec-tronic materials, properties that are missing in their prominent lead-containing counterparts. Their large ther-mopowers and high carrier mobilities also make them promising for thermoelectric applications. Here, we present a first-principles study of the lattice vibrations and thermal transport behaviors of Cs2SnI6 and gamma-CsSnI3, two prototypical compounds in this materials class. We show that conventional static zero temperature density functional theory (DFT) calculations severely underestimate the lattice thermal conductivities (kappa l) of these compounds, indicating the importance of dynamical effects. By calculating anharmonic renormalized phonon dispersions, we show that some optic phonons significantly harden with increasing temperature (T), which reduces the scattering of heat carrying phonons and enhances calculated kappa l values when compared with standard zero temperature DFT. Furthermore, we demonstrate that coherence contributions to kappa l, arising from wave like phonon tunneling, are important in both compounds. Overall, calculated kappa l with temperature-dependent inter-atomic force constants, built from particle and coherence contributions, are in good agreement with available measured data, for both magnitude and temperature dependence. Large anharmonicity combined with low phonon group velocities yield ultralow kappa l values, with room temperature values of 0.26 W/m-K and 0.72 W/m-K predicted for Cs2SnI6 and gamma-CsSnI3, respectively. We further show that the lattice dynamics of these compounds are highly anharmonic, largely mediated by rotation of the SnI6 octahedra and localized modes originating from Cs rattling motion. These thermal characteristics combined with their previously computed excellent electronic properties make these perovskites promising candidates for optoelectronic and room temperature thermoelectric applications.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000876484300002 Publication Date 2022-10-10  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2542-5293 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 11.5 Times cited Open Access Not_Open_Access  
  Notes Approved Most recent IF: 11.5  
  Call Number UA @ admin @ c:irua:192139 Serial 7329  
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Author Bafekry, A.; Obeid, M.; Nguyen, C.; Bagheri Tagani, M.; Ghergherehchi, M. url  doi
openurl 
  Title Graphene hetero-multilayer on layered platinum mineral Jacutingaite (Pt₂HgSe₃): Van der Waals heterostructures with novel optoelectronic and thermoelectric performances Type A1 Journal article
  Year 2020 Publication Journal Of Materials Chemistry A Abbreviated Journal J Mater Chem A  
  Volume 8 Issue 26 Pages 13248-13260  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Motivated by the recent successful synthesis of the layered platinum mineral jacutingaite (Pt2HgSe3), we have studied the optoelectronic, mechanical, and thermoelectric properties of graphene hetero-multilayer on Pt(2)HgSe(3)monolayer (PHS) heterostructures (LG/PHS) by using first-principles calculations. PHS is a topological insulator with a band gap of about 160 meV with fully relativistic calculations; when graphene layers are stacked on PHS, a narrow band gap of similar to 10-15 meV opens. In the presence of gate-voltage and out-of plane strain,i.e.pressure, the electronic properties are modified; the Dirac-cone of graphene can be shifted upwards (downward) to a lower (higher) binding energy. The absorption spectrum shows two peaks, which are located around 216 nm (5.74 eV) and protracted to 490 nm (2.53 eV), indicating that PHS could absorb more visible light. Increasing the number of graphene layers on PHS has a positive impact on the UV-vis light absorption and gives a clear red-shift with enhanced absorption intensity. To investigate the electronic performance of the heterostructure, the electrical conductance and thermopower of a device composed of graphene layers and PHS is examined by a combination of DFT and Green function formalism. The number of graphene layers can significantly tune the thermopower and electrical conductance. This analysis reveals that the heterostructures not only significantly affect the electronic properties, but they can also be used as an efficient way to modulate the optic and thermoelectric properties.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000546391600032 Publication Date 2020-05-28  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2050-7488; 2050-7496 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 11.9 Times cited 20 Open Access  
  Notes ; This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea Government (MSIT) (NRF-2017R1A2B2011989) and Vietnam National Foundation for Science and Technology Development (NAFOSTED) under grant number 103.01-2019.05. ; Approved Most recent IF: 11.9; 2020 IF: 8.867  
  Call Number UA @ admin @ c:irua:169755 Serial 6529  
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Author Sarikurt, S.; Kocabas, T.; Sevik, C. doi  openurl
  Title High-throughput computational screening of 2D materials for thermoelectrics Type A1 Journal article
  Year 2020 Publication Journal Of Materials Chemistry A Abbreviated Journal J Mater Chem A  
  Volume 8 Issue 37 Pages 19674-19683  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract High-performance thermoelectric materials are critical in recuperating the thermal losses in various machinery and promising in renewable energy applications. In this respect, the search for novel thermoelectric materials has attracted considerable attention. In particular, low dimensional materials have been proposed as potential candidates due to their unique and controllable thermal and electronic transport properties. The considerable potential of several two-dimensional materials as thermoelectric devices has already been uncovered and many new candidates that merit further research have been suggested. In this regard, we comprehensively investigate the thermoelectric coefficients and electronic fitness function (EFF) of a large family of structurally isotropic and anisotropic two-dimensional layered materials using density functional theory combined with semi-classical Boltzmann transport theory. With this high-throughput screening, we bring to light additional 2D crystals that haven't been previously classified as favorable TE materials. We predict that Pb2Se2, GeS2, As-2, NiS2, Hf2O6, Zr2O6, AsBrS, ISbTe, ISbSe, AsISe, and AsITe are promising isotropic thermoelectric materials due to their considerably high EFF values. In addition to these materials, Hf2Br4, Zr2Br4, Hf2Cl4, Zr2Cl4, Hf2O6, Zr(2)O(6)and Os(2)O(4)exhibit strong anisotropy and possess prominently high EFF values.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000573889000046 Publication Date 2020-08-31  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2050-7488; 2050-7496 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 11.9 Times cited Open Access  
  Notes Approved Most recent IF: 11.9; 2020 IF: 8.867  
  Call Number UA @ admin @ c:irua:193778 Serial 8039  
Permanent link to this record
 

 
Author Bals, S.; Van Aert, S.; Romero, C.P.; Lauwaet, K.; Van Bael, M.J.; Schoeters, B.; Partoens, B.; Yuecelen, E.; Lievens, P.; Van Tendeloo, G. pdf  url
doi  openurl
  Title Atomic scale dynamics of ultrasmall germanium clusters Type A1 Journal article
  Year 2012 Publication Nature communications Abbreviated Journal Nat Commun  
  Volume 3 Issue 897 Pages 897  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)  
  Abstract Starting from the gas phase, small clusters can be produced and deposited with huge flexibility with regard to composition, materials choice and cluster size. Despite many advances in experimental characterization, a detailed morphology of such clusters is still lacking. Here we present an atomic scale observation as well as the dynamical behaviour of ultrasmall germanium clusters. Using quantitative scanning transmission electron microscopy in combination with ab initio calculations, we are able to characterize the transition between different equilibrium geometries of a germanium cluster consisting of less than 25 atoms. Seven-membered rings, trigonal prisms and some smaller subunits are identified as possible building blocks that stabilize the structure.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000306099900024 Publication Date 2012-06-12  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2041-1723; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 12.124 Times cited 90 Open Access  
  Notes Fwo; Iap; Iwt Approved Most recent IF: 12.124; 2012 IF: 10.015  
  Call Number UA @ lucian @ c:irua:100340 Serial 183  
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Author Tongay, S.; Sahin, H.; Ko, C.; Luce, A.; Fan, W.; Liu, K.; Zhou, J.; Huang, Y.S.; Ho, C.H.; Yan, J.; Ogletree, D.F.; Aloni, S.; Ji, J.; Li, S.; Li, J.; Peeters, F.M.; Wu, J.; doi  openurl
  Title Monolayer behaviour in bulk ReS2 due to electronic and vibrational decoupling Type A1 Journal article
  Year 2014 Publication Nature communications Abbreviated Journal Nat Commun  
  Volume 5 Issue Pages 3252  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Semiconducting transition metal dichalcogenides consist of monolayers held together by weak forces where the layers are electronically and vibrationally coupled. Isolated monolayers show changes in electronic structure and lattice vibration energies, including a transition from indirect to direct bandgap. Here we present a new member of the family, rhenium disulphide (ReS2), where such variation is absent and bulk behaves as electronically and vibrationally decoupled monolayers stacked together. From bulk to monolayers, ReS2 remains direct bandgap and its Raman spectrum shows no dependence on the number of layers. Interlayer decoupling is further demonstrated by the insensitivity of the optical absorption and Raman spectrum to interlayer distance modulated by hydrostatic pressure. Theoretical calculations attribute the decoupling to Peierls distortion of the 1T structure of ReS2, which prevents ordered stacking and minimizes the interlayer overlap of wavefunctions. Such vanishing interlayer coupling enables probing of two-dimensional-like systems without the need for monolayers.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000332666700010 Publication Date 2014-02-06  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2041-1723; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 12.124 Times cited 806 Open Access  
  Notes ; This work was supported by the United States Department of Energy Early Career Award DE-FG02-11ER46796. The high pressure part of this work was supported by COMPRES, the Consortium for Materials Properties Research in Earth Sciences, under National Science Foundation Cooperative Agreement EAR 11-577758. The electron microscopy and nano-Auger measurements were supported by the user programme at the Molecular Foundry, which was supported by the Office of Science, Office of Basic Energy Sciences, of the United States Department of Energy under contract no. DE-AC02-05CH11231. S. A. gratefully acknowledges Dr Virginia Altoe of the Molecular Foundry for help with the TEM data acquisition and analysis. J.L. acknowledges support from the Natural Science Foundation of China for Distinguished Young Scholar (grant nos. 60925016 and 91233120). Y.-S.H. and C.-H. H. acknowledge support from the National Science Council of Taiwan under project nos. NSC 100-2112-M-011-001-MY3 and NSC 101-2221-E-011-052-MY3. H. S. was supported by the FWO Pegasus Marie Curie Long Fellowship programme. The DFT work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem programme of the Flemish government. Computational resources were partially provided by TUBITAK ULAKBIM, High Performance and Grid Computing Centre. ; Approved Most recent IF: 12.124; 2014 IF: 11.470  
  Call Number UA @ lucian @ c:irua:119247 Serial 2192  
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Author Neek-Amal, M.; Xu, P.; Schoelz, J.K.; Ackerman, M.L.; Barber, S.D.; Thibado, P.M.; Sadeghi, A.; Peeters, F.M. doi  openurl
  Title Thermal mirror buckling in freestanding graphene locally controlled by scanning tunnelling microscopy Type A1 Journal article
  Year 2014 Publication Nature communications Abbreviated Journal Nat Commun  
  Volume 5 Issue Pages 4962  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Knowledge of and control over the curvature of ripples in freestanding graphene are desirable for fabricating and designing flexible electronic devices, and recent progress in these pursuits has been achieved using several advanced techniques such as scanning tunnelling microscopy. The electrostatic forces induced through a bias voltage (or gate voltage) were used to manipulate the interaction of freestanding graphene with a tip (substrate). Such forces can cause large movements and sudden changes in curvature through mirror buckling. Here we explore an alternative mechanism, thermal load, to control the curvature of graphene. We demonstrate thermal mirror buckling of graphene by scanning tunnelling microscopy and large-scale molecular dynamic simulations. The negative thermal expansion coefficient of graphene is an essential ingredient in explaining the observed effects. This new control mechanism represents a fundamental advance in understanding the influence of temperature gradients on the dynamics of freestanding graphene and future applications with electro-thermal-mechanical nanodevices.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000342984800018 Publication Date 2014-09-17  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2041-1723; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 12.124 Times cited 36 Open Access  
  Notes ; Financial support for this study was provided, in part, by the Office of Naval Research under grant N00014-10-1-0181, the National Science Foundation under grant DMR-0855358, the EU-Marie Curie IIF postdoc Fellowship/299855 (for M. N.-A.), the ESF-EuroGRAPHENE project CONGRAN, the Flemish Science Foundation (FWO-Vl) and the Methusalem Foundation of the Flemish Government. M.N.-A. has also been supported partially by BOF project of University of Antwerp number 28033. ; Approved Most recent IF: 12.124; 2014 IF: 11.470  
  Call Number UA @ lucian @ c:irua:121121 Serial 3628  
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Author Xu, P.; Neek-Amal, M.; Barber, S.D.; Schoelz, J.K.; Ackerman, M.L.; Thibado, P.M.; Sadeghi, A.; Peeters, F.M. doi  openurl
  Title Unusual ultra-low-frequency fluctuations in freestanding graphene Type A1 Journal article
  Year 2014 Publication Nature communications Abbreviated Journal Nat Commun  
  Volume 5 Issue Pages 3720  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Intrinsic ripples in freestanding graphene have been exceedingly difficult to study. Individual ripple geometry was recently imaged using scanning tunnelling microscopy, but these measurements are limited to static configurations. Thermally-activated flexural phonon modes should generate dynamic changes in curvature. Here we show how to track the vertical movement of a one-square-angstrom region of freestanding graphene using scanning tunnelling microscopy, thereby allowing measurement of the out-of-plane time trajectory and fluctuations over long time periods. We also present a model from elasticity theory to explain the very-low-frequency oscillations. Unexpectedly, we sometimes detect a sudden colossal jump, which we interpret as due to mirror buckling. This innovative technique provides a much needed atomic-scale probe for the time-dependent behaviours of intrinsic ripples. The discovery of this novel progenitor represents a fundamental advance in the use of scanning tunnelling microscopy, which together with the application of a thermal load provides a low-frequency nano-resonator.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000335223200007 Publication Date 2014-04-28  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2041-1723; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 12.124 Times cited 62 Open Access  
  Notes ; This work was financially supported, in part, by the Office of Naval Research under grant N00014-10-1-0181, the National Science Foundation under grant DMR-0855358, the EU-Marie Curie IIF postdoc Fellowship/299855 (for M.N.-A.), the ESF-Euro-GRAPHENE project CONGRAN, the Flemish Science Foundation (FWO-Vl) and the Methusalem Foundation of the Flemish Government. ; Approved Most recent IF: 12.124; 2014 IF: 11.470  
  Call Number UA @ lucian @ c:irua:117201 Serial 3819  
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Author Buh, J.; Kabanov, V.; Baranov, V.; Mrzel, A.; Kovic, A.; Mihailovic, D. url  doi
openurl 
  Title Control of switching between metastable superconducting states in delta-MoN nanowires Type A1 Journal article
  Year 2015 Publication Nature communications Abbreviated Journal Nat Commun  
  Volume 6 Issue 6 Pages 10250  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract The superconducting state in one-dimensional nanosystems is very delicate. While fluctuations of the phase of the superconducting wave function lead to the spontaneous decay of persistent supercurrents in thin superconducting wires and nanocircuits, discrete phase-slip fluctuations can also lead to more exotic phenomena, such as the appearance of metastable superconducting states in current-bearing wires. Here we show that switching between different metastable superconducting states in d-MoN nanowires can be very effectively manipulated by introducing small amplitude electrical noise. Furthermore, we show that deterministic switching between metastable superconducting states with different numbers of phase-slip centres can be achieved in both directions with small electrical current pulse perturbations of appropriate polarity. The observed current-controlled bi-stability is in remarkable agreement with theoretically predicted trajectories of the system switching between different limit cycle solutions of a model one-dimensional superconductor.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000367576600002 Publication Date 2015-12-21  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2041-1723 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 12.124 Times cited 8 Open Access  
  Notes ; ; Approved Most recent IF: 12.124; 2015 IF: 11.470  
  Call Number UA @ lucian @ c:irua:131108 Serial 4156  
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Author Willhammar, T.; Sentosun, K.; Mourdikoudis, S.; Goris, B.; Kurttepeli, M.; Bercx, M.; Lamoen, D.; Partoens, B.; Pastoriza-Santos, I.; Pérez-Juste, J.; Liz-Marzán, L.M.; Bals, S.; Van Tendeloo, G. pdf  url
doi  openurl
  Title Structure and vacancy distribution in copper telluride nanoparticles influence plasmonic activity in the near-infrared Type A1 Journal article
  Year 2017 Publication Nature communications Abbreviated Journal Nat Commun  
  Volume 8 Issue 8 Pages 14925  
  Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)  
  Abstract Copper chalcogenides find applications in different domains including photonics, photothermal therapy and photovoltaics. CuTe nanocrystals have been proposed as an alternative to noble metal particles for plasmonics. Although it is known that deviations from stoichiometry are a prerequisite for plasmonic activity in the near-infrared, an accurate description of the material and its (optical) properties is hindered by an insufficient understanding of the atomic structure and the influence of defects, especially for materials in their nanocrystalline form. We demonstrate that the structure of Cu1.5±xTe nanocrystals canbe determined using electron diffraction tomography. Real-space high-resolution electron tomography directly reveals the three-dimensional distribution of vacancies in the structure. Through first-principles density functional theory, we furthermore demonstrate that the influence of these vacancies on the optical properties of the nanocrystals is determined. Since our methodology is applicable to a variety of crystalline nanostructured materials, it is expected to provide unique insights concerning structure–property correlations.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000397799700001 Publication Date 2017-03-30  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2041-1723 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 12.124 Times cited 37 Open Access OpenAccess  
  Notes The work was financially supported by the European Research Council through an ERC Starting Grant (#335078-COLOURATOMS). T.W. acknowledges the Swedish Research Council for an international postdoc grant. We acknowledge financial support of FWO-Vlaanderen through project G.0216.14N, G.0369.15N and a postdoctoral research grant to B.G. The computational resources and services used in this work were provided by the VSC (Flemish Supercomputer Center) and the HPC infrastructure of the University of Antwerp (CalcUA), both funded by the FWO-Vlaanderen and the Flemish Government–Department EWI. The work was further supported by the Spanish MINECO (MAT2013-45168-R). S.M. thanks the Action ooSupporting Postdoctoral Researchers44 of the Operational Program ‘Education and Lifelong Learning’ (Action’s Beneficiary: General Secretariat for Research and Technology of Greece), which was co-financed by the European Social Fund (ESF) and the Greek State. (ROMEO:green; preprint:; postprint:can ; pdfversion:can); ECAS_Sara Approved Most recent IF: 12.124  
  Call Number EMAT @ emat @ c:irua:142203UA @ admin @ c:irua:142203 Serial 4538  
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Author Ghorbanfekr-Kalashami, H.; Vasu, K.S.; Nair, R.R.; Peeters, F.M.; Neek-Amal, M. url  doi
openurl 
  Title Dependence of the shape of graphene nanobubbles on trapped substance Type A1 Journal article
  Year 2017 Publication Nature communications Abbreviated Journal Nat Commun  
  Volume 8 Issue 8 Pages 15844  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Van der Waals (vdW) interaction between two-dimensional crystals (2D) can trap substances in high pressurized (of order 1 GPa) on nanobubbles. Increasing the adhesion between the 2D crystals further enhances the pressure and can lead to a phase transition of the trapped material. We found that the shape of the nanobubble can depend critically on the properties of the trapped substance. In the absence of any residual strain in the top 2D crystal, flat nanobubbles can be formed by trapped long hydrocarbons (that is, hexadecane). For large nanobubbles with radius 130 nm, our atomic force microscopy measurements show nanobubbles filled with hydrocarbons (water) have a cylindrical symmetry (asymmetric) shape which is in good agreement with our molecular dynamics simulations. This study provides insights into the effects of the specific material and the vdW pressure on the microscopic details of graphene bubbles.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000403417500001 Publication Date 2017-06-16  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2041-1723 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 12.124 Times cited 44 Open Access  
  Notes We acknowledge fruitful discussion with Irina Grigorieva and Andre K. Geim. This work was supported by the Flemish Science Foundation (FWO-Vl) and the Methusalem program, the Royal Society and the Engineering and Physical Sciences Research Council, UK (EP/K016946/1). M.N.-A. was supported by Iran National Science Foundation (INSF). Approved Most recent IF: 12.124  
  Call Number CMT @ cmt @ c:irua:144189 Serial 4580  
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Author Chirayath, V.A.; Callewaert, V.; Fairchild, A.J.; Chrysler, M.D.; Gladen, R.W.; Mcdonald, A.D.; Imam, S.K.; Shastry, K.; Koymen, A.R.; Saniz, R.; Barbiellini, B.; Rajeshwar, K.; Partoens, B.; Weiss, A.H. pdf  url
doi  openurl
  Title Auger electron emission initiated by the creation of valence-band holes in graphene by positron annihilation Type A1 Journal article
  Year 2017 Publication Nature communications Abbreviated Journal Nat Commun  
  Volume 8 Issue 8 Pages 16116  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Auger processes involving the filling of holes in the valence band are thought to make important contributions to the low-energy photoelectron and secondary electron spectrum from many solids. However, measurements of the energy spectrum and the efficiency with which electrons are emitted in this process remain elusive due to a large unrelated background resulting from primary beam-induced secondary electrons. Here, we report the direct measurement of the energy spectra of electrons emitted from single layer graphene as a result of the decay of deep holes in the valence band. These measurements were made possible by eliminating competing backgrounds by employing low-energy positrons (<1.25 eV) to create valence-band holes by annihilation. Our experimental results, supported by theoretical calculations, indicate that between 80 and 100% of the deep valence-band holes in graphene are filled via an Auger transition.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000405398200001 Publication Date 2017-07-13  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2041-1723 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 12.124 Times cited 20 Open Access  
  Notes The experiments in this work were supported by the grant NSF DMR 1508719. A.H.W and A.R.K. gratefully acknowledge support for the building of advanced positron beam through the grant NSF DMR MRI 1338130. V.C. and R.S. were supported by the FWO-Vlaanderen through Project No. G. 0224.14N. The computational resources and services used in this work were in part 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 (EWI Department). The work at Northeastern University was supported by the US Department of Energy (DOE), Office of Science, Basic Energy Sciences grant number DE-FG02-07ER46352 (core research), and benefited from Northeastern University’s Advanced Scientific Computation Center (ASCC), the NERSC supercomputing center through DOE grant number DE-AC02-05CH11231, and support (applications to layered materials) from the DOE EFRC: Center for the Computational Design of Functional Layered Materials (CCDM) under DE-SC0012575. Approved Most recent IF: 12.124  
  Call Number CMT @ cmt @ c:irua:144625 Serial 4627  
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Author Wu, K.; Torun, E.; Sahin, H.; Chen, B.; Fan, X.; Pant, A.; Wright, D.P.; Aoki, T.; Peeters, F.M.; Soignard, E.; Tongay, S. url  doi
openurl 
  Title Unusual lattice vibration characteristics in whiskers of the pseudo-one-dimensional titanium trisulfide TiS3 Type A1 Journal article
  Year 2016 Publication Nature communications Abbreviated Journal Nat Commun  
  Volume 7 Issue Pages 12952  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Transition metal trichalcogenides form a class of layered materials with strong in-plane anisotropy. For example, titanium trisulfide (TiS3) whiskers are made out of weakly interacting TiS3 layers, where each layer is made of weakly interacting quasi-one-dimensional chains extending along the b axis. Here we establish the unusual vibrational properties of TiS3 both experimentally and theoretically. Unlike other two-dimensional systems, the Raman active peaks of TiS3 have only out-of-plane vibrational modes, and interestingly some of these vibrations involve unique rigid-chain vibrations and S-S molecular oscillations. High-pressure Raman studies further reveal that the A(g)(S-S) S-S molecular mode has an unconventional negative pressure dependence, whereas other peaks stiffen as anticipated. Various vibrational modes are doubly degenerate at ambient pressure, but the degeneracy is lifted at high pressures. These results establish the unusual vibrational properties of TiS3 with strong in-plane anisotropy, and may have relevance to understanding of vibrational properties in other anisotropic two-dimensional material systems.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000385444300004 Publication Date 2016-09-22  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2041-1723 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 12.124 Times cited 50 Open Access  
  Notes ; S.T. acknowledges support from the National Science Foundation (DMR-1552220) and (CMMI-1561839). F.M.P., H.S. and E.T. were supported by the Flemish Science Foundation (FWO-Vl). Computational resources were partially provided by TUBITAK ULAKBIM, High Performance and Grid Computing Center (TR-Grid e Infrastructure). H.S. acknowledges support from Bilim Akademisi-The Science Academy, Turkey under the BAGEP programme. F.P. acknowledges the funding from Flemish Science Foundation (FWO-Vl). K.W. acknowledges helpful discussions with H. Cai, W. Kong and X. Meng. We gratefully acknowledge the use of facilities within the LeRoy Eyring Center for Solid State Science at Arizona State University. ; Approved Most recent IF: 12.124  
  Call Number UA @ lucian @ c:irua:144662 Serial 4700  
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Author Embon, L.; Anahory, Y.; Jelić, Z.L.; Lachman, E.O.; Myasoedov, Y.; Huber, M.E.; Mikitik, G.P.; Silhanek, A.V.; Milošević, M.V.; Gurevich, A.; Zeldov, E. url  doi
openurl 
  Title Imaging of super-fast dynamics and flow instabilities of superconducting vortices Type A1 Journal article
  Year 2017 Publication Nature communications Abbreviated Journal Nat Commun  
  Volume 8 Issue Pages 85  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Quantized magnetic vortices driven by electric current determine key electromagnetic properties of superconductors. While the dynamic behavior of slow vortices has been thoroughly investigated, the physics of ultrafast vortices under strong currents remains largely unexplored. Here, we use a nanoscale scanning superconducting quantum interference device to image vortices penetrating into a superconducting Pb film at rates of tens of GHz and moving with velocities of up to tens of km/s, which are not only much larger than the speed of sound but also exceed the pair-breaking speed limit of superconducting condensate. These experiments reveal formation of mesoscopic vortex channels which undergo cascades of bifurcations as the current and magnetic field increase. Our numerical simulations predict metamorphosis of fast Abrikosov vortices into mixed Abrikosov-Josephson vortices at even higher velocities. This work offers an insight into the fundamental physics of dynamic vortex states of superconductors at high current densities, crucial for many applications.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000405900400002 Publication Date 2017-07-13  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2041-1723 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 12.124 Times cited 124 Open Access  
  Notes ; We would like to thank M.L. Rappaport for fruitful discussions and technical support. This work was supported by the US-Israel Binational Science Foundation (BSF) grant No. 2014155 and the Israel Science Foundation grant No. 132/14. A.G. was also supported by the United States Department of Energy under Grant No. DE-SC0010081. M.V.M. acknowledges support from Research Foundation-Flanders (FWO). 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. This work benefited from the support of COST action MP-1201. ; Approved Most recent IF: 12.124  
  Call Number UA @ lucian @ c:irua:144832 Serial 4720  
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Author Zalalutdinov, M.K.; Robinson, J.T.; Fonseca, J.J.; LaGasse, S.W.; Pandey, T.; Lindsay, L.R.; Reinecke, T.L.; Photiadis, D.M.; Culbertson, J.C.; Cress, C.D.; Houston, B.H. url  doi
openurl 
  Title Acoustic cavities in 2D heterostructures Type A1 Journal article
  Year 2021 Publication Nature Communications Abbreviated Journal Nat Commun  
  Volume 12 Issue 1 Pages 3267  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Two-dimensional (2D) materials offer unique opportunities in engineering the ultrafast spatiotemporal response of composite nanomechanical structures. In this work, we report on high frequency, high quality factor (Q) 2D acoustic cavities operating in the 50-600GHz frequency (f) range with f x Q up to 1 x 10(14). Monolayer steps and material interfaces expand cavity functionality, as demonstrated by building adjacent cavities that are isolated or strongly-coupled, as well as a frequency comb generator in MoS2/h-BN systems. Energy dissipation measurements in 2D cavities are compared with attenuation derived from phonon-phonon scattering rates calculated using a fully microscopic ab initio approach. Phonon lifetime calculations extended to low frequencies (<1THz) and combined with sound propagation analysis in ultrathin plates provide a framework for designing acoustic cavities that approach their fundamental performance limit. These results provide a pathway for developing platforms employing phonon-based signal processing and for exploring the quantum nature of phonons. Here, authors report on acoustic cavities in 2D materials operating in the 50-600GHz range and show that quality factors approach the limit set by lattice anharmonicity. Functionality expanded by heterogeneities (steps and interfaces) is demonstrated through coupled cavities and frequency comb generation.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000660772400004 Publication Date 2021-06-01  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2041-1723 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 12.124 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 12.124  
  Call Number UA @ admin @ c:irua:179597 Serial 6968  
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Author Sun, P.Z.; Yagmurcukardes, M.; Zhang, R.; Kuang, W.J.; Lozada-Hidalgo, M.; Liu, B.L.; Cheng, H.-M.; Wang, F.C.; Peeters, F.M.; Grigorieva, I.V.; Geim, A.K. url  doi
openurl 
  Title Exponentially selective molecular sieving through angstrom pores Type A1 Journal article
  Year 2021 Publication Nature Communications Abbreviated Journal Nat Commun  
  Volume 12 Issue 1 Pages 7170  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Two-dimensional crystals with angstrom-scale pores are widely considered as candidates for a next generation of molecular separation technologies aiming to provide extreme, exponentially large selectivity combined with high flow rates. No such pores have been demonstrated experimentally. Here we study gas transport through individual graphene pores created by low intensity exposure to low kV electrons. Helium and hydrogen permeate easily through these pores whereas larger species such as xenon and methane are practically blocked. Permeating gases experience activation barriers that increase quadratically with molecules' kinetic diameter, and the effective diameter of the created pores is estimated as similar to 2 angstroms, about one missing carbon ring. Our work reveals stringent conditions for achieving the long sought-after exponential selectivity using porous two-dimensional membranes and suggests limits on their possible performance. Two-dimensional membranes with angstrom-sized pores are predicted to combine high permeability with exceptional selectivity, but experimental demonstration has been challenging. Here the authors realize angstrom-sized pores in monolayer graphene and demonstrate gas transport with activation barriers increasing quadratically with the molecular kinetic diameter.  
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  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000728562700016 Publication Date 2021-12-09  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2041-1723 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 12.124 Times cited 10 Open Access OpenAccess  
  Notes Approved Most recent IF: 12.124  
  Call Number UA @ admin @ c:irua:184840 Serial 6989  
Permanent link to this record
 

 
Author Lyu, Y.-Y.; Jiang, J.; Wang, Y.-L.; Xiao, Z.-L.; Dong, S.; Chen, Q.-H.; Milošević, M.V.; Wang, H.; Divan, R.; Pearson, J.E.; Wu, P.; Peeters, F.M.; Kwok, W.-K. url  doi
openurl 
  Title Superconducting diode effect via conformal-mapped nanoholes Type A1 Journal article
  Year 2021 Publication Nature Communications Abbreviated Journal Nat Commun  
  Volume 12 Issue 1 Pages 2703  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract A superconducting diode is an electronic device that conducts supercurrent and exhibits zero resistance primarily for one direction of applied current. Such a dissipationless diode is a desirable unit for constructing electronic circuits with ultralow power consumption. However, realizing a superconducting diode is fundamentally and technologically challenging, as it usually requires a material structure without a centre of inversion, which is scarce among superconducting materials. Here, we demonstrate a superconducting diode achieved in a conventional superconducting film patterned with a conformal array of nanoscale holes, which breaks the spatial inversion symmetry. We showcase the superconducting diode effect through switchable and reversible rectification signals, which can be three orders of magnitude larger than that from a flux-quantum diode. The introduction of conformal potential landscapes for creating a superconducting diode is thereby proven as a convenient, tunable, yet vastly advantageous tool for superconducting electronics. This could be readily applicable to any superconducting materials, including cuprates and iron-based superconductors that have higher transition temperatures and are desirable in device applications. A superconducting diode is dissipationless and desirable for electronic circuits with ultralow power consumption, yet it remains challenging to realize it. Here, the authors achieve a superconducting diode in a conventional superconducting film patterned with a conformal array of nanoscale holes.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000658724200018 Publication Date 2021-05-11  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2041-1723 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 12.124 Times cited 23 Open Access OpenAccess  
  Notes Approved Most recent IF: 12.124  
  Call Number UA @ admin @ c:irua:179611 Serial 7024  
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Author Lee, Y.; Forte, J.D.'arf S.; Chaves, A.; Kumar, A.; Tran, T.T.; Kim, Y.; Roy, S.; Taniguchi, T.; Watanabe, K.; Chernikov, A.; Jang, J.I.; Low, T.; Kim, J. url  doi
openurl 
  Title Boosting quantum yields in two-dimensional semiconductors via proximal metal plates Type A1 Journal article
  Year 2021 Publication Nature Communications Abbreviated Journal Nat Commun  
  Volume 12 Issue 1 Pages 7095  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract The short exciton lifetime and strong exciton-exciton interaction in transition metal dichalcogenides limit the efficiency of exciton emission. Here, the authors show that exciton-exciton interaction in monolayer WS2 can be screened using proximal metal plates, leading to an improved quantum yield. Monolayer transition metal dichalcogenides (1L-TMDs) have tremendous potential as atomically thin, direct bandgap semiconductors that can be used as convenient building blocks for quantum photonic devices. However, the short exciton lifetime due to the defect traps and the strong exciton-exciton interaction in TMDs has significantly limited the efficiency of exciton emission from this class of materials. Here, we show that exciton-exciton interaction in 1L-WS2 can be effectively screened using an ultra-flat Au film substrate separated by multilayers of hexagonal boron nitride. Under this geometry, induced dipolar exciton-exciton interaction becomes quadrupole-quadrupole interaction because of effective image dipoles formed within the metal. The suppressed exciton-exciton interaction leads to a significantly improved quantum yield by an order of magnitude, which is also accompanied by a reduction in the exciton-exciton annihilation (EEA) rate, as confirmed by time-resolved optical measurements. A theoretical model accounting for the screening of the dipole-dipole interaction is in a good agreement with the dependence of EEA on exciton densities. Our results suggest that fundamental EEA processes in the TMD can be engineered through proximal metallic screening, which represents a practical approach towards high-efficiency 2D light emitters.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000728559600014 Publication Date 2021-12-07  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2041-1723 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 12.124 Times cited Open Access OpenAccess  
  Notes Approved Most recent IF: 12.124  
  Call Number UA @ admin @ c:irua:184870 Serial 7566  
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Author Wang, F.; Wang, C.; Chaves, A.; Song, C.; Zhang, G.; Huang, S.; Lei, Y.; Xing, Q.; Mu, L.; Xie, Y.; Yan, H. doi  openurl
  Title Prediction of hyperbolic exciton-polaritons in monolayer black phosphorus Type A1 Journal article
  Year 2021 Publication Nature Communications Abbreviated Journal Nat Commun  
  Volume 12 Issue 1 Pages 5628  
  Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)  
  Abstract Hyperbolic polaritons exhibit large photonic density of states and can be collimated in certain propagation directions. The majority of hyperbolic polaritons are sustained in man-made metamaterials. However, natural-occurring hyperbolic materials also exist. Particularly, natural in-plane hyperbolic polaritons in layered materials have been demonstrated in MoO3 and WTe2, which are based on phonon and plasmon resonances respectively. Here, by determining the anisotropic optical conductivity (dielectric function) through optical spectroscopy, we predict that monolayer black phosphorus naturally hosts hyperbolic exciton-polaritons due to the pronounced in-plane anisotropy and strong exciton resonances. We simultaneously observe a strong and sharp ground state exciton peak and weaker excited states in high quality monolayer samples in the reflection spectrum, which enables us to determine the exciton binding energy of similar to 452 meV. Our work provides another appealing platform for the in-plane natural hyperbolic polaritons, which is based on excitons rather than phonons or plasmons.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language Wos 000698984500003 Publication Date 2021-10-12  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2041-1723 ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 12.124 Times cited Open Access Not_Open_Access  
  Notes Approved Most recent IF: 12.124  
  Call Number UA @ admin @ c:irua:191688 Serial 8404  
Permanent link to this record
 

 
Author Zarenia, M.; Pereira, J.M.; Peeters, F.M.; Farias, G.A. doi  openurl
  Title Electrostatically confined quantum rings in bilayer graphene Type A1 Journal article
  Year 2009 Publication Nano letters Abbreviated Journal Nano Lett  
  Volume 9 Issue 12 Pages 4088-4092  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract We propose a new system where electron and hole states are electrostatically confined into a quantum ring in bilayer graphene. These structures can be created by tuning the gap of the graphene bilayer using nanostructured gates or by position-dependent doping. The energy levels have a magnetic field (B0) dependence that is strikingly distinct from that of usual semiconductor quantum rings. In particular, the eigenvalues are not invariant under a B0 ¨ −B0 transformation and, for a fixed total angular momentum index m, their field dependence is not parabolic, but displays two minima separated by a saddle point. The spectra also display several anticrossings, which arise due to the overlap of gate-confined and magnetically confined states.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Washington Editor  
  Language Wos 000272395400023 Publication Date 2009-08-25  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1530-6984;1530-6992; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 12.712 Times cited 42 Open Access  
  Notes Approved Most recent IF: 12.712; 2009 IF: 9.991  
  Call Number UA @ lucian @ c:irua:80318 Serial 1024  
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Author Peelaers, H.; Partoens, B.; Peeters, F.M. doi  openurl
  Title Formation and segregation energies of B and P doped and BP codoped silicon nanowires Type A1 Journal article
  Year 2006 Publication Nano letters Abbreviated Journal Nano Lett  
  Volume 6 Issue 12 Pages 2781-2784  
  Keywords A1 Journal article; Condensed Matter Theory (CMT)  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Washington Editor  
  Language Wos 000242786500026 Publication Date 2006-11-02  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1530-6984;1530-6992; ISBN Additional Links UA library record; WoS full record; WoS citing articles  
  Impact Factor (up) 12.712 Times cited 94 Open Access  
  Notes Approved Most recent IF: 12.712; 2006 IF: 9.960  
  Call Number UA @ lucian @ c:irua:62381 Serial 1248  
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