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Author Lukyanchuk, I.; Vinokur, V.M.; Rydh, A.; Xie, R.; Milošević, M.V.; Welp, U.; Zach, M.; Xiao, Z.L.; Crabtree, G.W.; Bending, S.J.; Peeters, F.M.; Kwok, W.K.
Title Rayleigh instability of confined vortex droplets in critical superconductors Type A1 Journal article
Year 2015 Publication Nature physics Abbreviated Journal Nat Phys
Volume 11 Issue 11 Pages 21-25
Keywords A1 Journal article; Condensed Matter Theory (CMT)
Abstract Depending on the Ginzburg-Landau parameter kappa, superconductors can either be fully diamagnetic if kappa < 1/root 2 (type I superconductors) or allow magnetic flux to penetrate through Abrikosov vortices if kappa > 1/root 2 (type II superconductors; refs 1,2). At the Bogomolny critical point, kappa = kappa(c) = 1/root 2, a state that is infinitely degenerate with respect to vortex spatial configurations arises(3,4). Despite in-depth investigations of conventional type I and type II superconductors, a thorough understanding of the magnetic behaviour in the near-Bogomolny critical regime at kappa similar to kappa(c) remains lacking. Here we report that in confined systems the critical regime expands over a finite interval of kappa forming a critical superconducting state. We show that in this state, in a sample with dimensions comparable to the vortex core size, vortices merge into a multi-quanta droplet, which undergoes Rayleigh instability(5) on increasing kappa and decays by emitting single vortices. Superconducting vortices realize Nielsen-Olesen singular solutions of the Abelian Higgs model, which is pervasive in phenomena ranging from quantum electrodynamics to cosmology(6-9). Our study of the transient dynamics of Abrikosov-Nielsen-Olesen vortices in systems with boundaries promises access to non-trivial effects in quantum field theory by means of bench-top laboratory experiments.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language (up) Wos 000346831100018 Publication Date 2014-11-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1745-2473;1745-2481; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 22.806 Times cited 20 Open Access
Notes ; We would like to thank N. Nekrasov for illuminating discussions. The work was supported by the US Department of Energy, Office of Science Materials Sciences and Engineering Division (V.M.V., W.K.K., U.W., R.X., M.Z., Z.L.X., G.W.C. and partially I.L. through the Materials Theory Institute), by FP7-IRSES-SIMTECH and ITN-NOTEDEV programs (I.L.), and by the Flemish Science Foundation (FWO-Vlaanderen) (M.V.M. and F.M.P.). ; Approved Most recent IF: 22.806; 2015 IF: 20.147
Call Number c:irua:122791 c:irua:122791 Serial 2815
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Author Zhang, L.; Lin, B.-C.; Wu, Y.-F.; Wu, H.; Huang, T.-W.; Chang, C.-R.; Ke, X.; Kurttepeli, M.; Tendeloo, G.V.; Xu, J.; Yu, D.; Liao, Z.-M.
Title Electronic Coupling between Graphene and Topological Insulator Induced Anomalous Magnetotransport Properties Type A1 Journal article
Year 2017 Publication ACS nano Abbreviated Journal Acs Nano
Volume 11 Issue 11 Pages 6277-6285
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract It has been theoretically proposed that the spin textures of surface states in a topological insulator can be directly transferred to graphene by means of the proximity effect, which is very important for realizing the two-dimensional topological insulator based on graphene. Here we report the anomalous magnetotransport properties of graphene-topological insulator Bi2Se3 heterojunctions, which are sensitive to the electronic coupling between graphene and the topological surface state. The coupling between the p_z orbitals of graphene and the p orbitals of the surface states on the Bi2Se3 bottom surface can be enhanced by applying a perpendicular negative magnetic field, resulting in a giant negative magnetoresistance at the Dirac point up to about -91%. Obvious resistances dip in the transfer curve at the Dirac point is also observed in the hybrid devices, which is consistent with theoretical predictions of the distorted Dirac bands with nontrivial spin textures inherited from the Bi2Se3 surface states.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language (up) Wos 000404808000110 Publication Date 2017-05-10
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1936-0851 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 13.942 Times cited 12 Open Access OpenAccess
Notes ; This work was supported by National Key Research and Development Program of China (Nos. 2016YFA0300802, 2013CB934600) and NSFC (No. 11234001). ; Approved Most recent IF: 13.942
Call Number EMAT @ emat @ c:irua:143192 Serial 4569
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Author van der Torren, A.J.H.; Liao, Z.; Xu, C.; Gauquelin, N.; Yin, C.; Aarts, J.; van der Molen, S.J.
Title Formation of a conducting LaAlO3/SrTiO3 interface studied by low-energy electron reflection during growth Type A1 Journal Article
Year 2017 Publication Physical Review Materials Abbreviated Journal Phys. Rev. Materials
Volume 1 Issue 7 Pages 075001
Keywords A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ;
Abstract The two-dimensional electron gas occurring between the band insulators SrTiO 3 and LaAlO 3 continues to attract considerable interest, due to the possibility of dynamic control over the carrier density, and the ensuing phenomena such as magnetism and superconductivity. The formation of this conducting interface is sensitive to the growth conditions, but despite numerous investigations, there are still questions about the details of the physics involved. In particular, not much is known about the electronic structure of the growing LaAlO 3 layer at the growth temperature (around 800 ◦ C) in oxygen (pressure around 5 × 10 −5 mbar), since analysis techniques at these conditions are not readily available. We developed a pulsed laser deposition system inside a low-energy electron microscope in order to study this issue. The setup allows for layer-by-layer growth control and in-situ measurements of the angle-dependent electron reflection intensity, which can be used as a fingerprint of the electronic structure of the surface layers during growth. By using different substrate terminations and growth conditions we observe two families of reflectivity maps, which we can connect either to samples with an AlO 2 -rich surface and a conducting interface; or to samples with a LaO-rich surface and an insulating interface. Our observations emphasize that substrate termination and stoichiometry determine the electronic structure of the growing layer, and thereby the conductance of the interface.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language (up) Wos 000418770200003 Publication Date 2017-12-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2475-9953 ISBN Additional Links
Impact Factor Times cited 2 Open Access Not_Open_Access
Notes Nederlandse Organisatie voor Wetenschappelijk Onderzoek; Fonds Wetenschappelijk Onderzoek, G.0044.13N ; European Cooperation in Science and Technology, MP 1308 ; We want to acknowledge Ruud Tromp, Daniel Gee- len, Johannes Jobst, Regina Dittmann, Gert Jan Koster, Guus Rijnders and Jo Verbeek for discussions and ad- vice and Ruud van Egmond and Marcel Hesselberth for technical assistance. This work was supported by the Netherlands Organization for Scientific Research (NWO) by means of an ”NWO Groot” grant and by the Leiden- Delft Consortium NanoFront. The work is part of the re- search programmes NWOnano and DESCO, which are fi- nanced by NWO. N.G. acknowledges funding through the GOA project “Solarpaint” of the University of Antwerp and from the FWO project G.0044.13N (Charge order- ing). The microscope used in this work was partly funded by the Hercules Fund from the Flemish Government. We would also like to acknowledge networking support by the COST Action MP 1308 (COST TO-BE). Approved Most recent IF: NA
Call Number EMAT @ emat @ Serial 4903
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Author Song, H.-D.; Wu, Y.-F.; Yang, X.; Ren, Z.; Ke, X.; Kurttepeli, M.; Tendeloo, G.V.; Liu, D.; Wu, H.-C.; Yan, B.; Wu, X.; Duan, C.-G.; Han, G.; Liao, Z.-M.; Yu, D.
Title Asymmetric Modulation on Exchange Field in a Graphene/BiFeO3Heterostructure by External Magnetic Field Type A1 Journal article
Year 2018 Publication Nano letters Abbreviated Journal Nano Lett
Volume 18 Issue 4 Pages 2435-2441
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Graphene, having all atoms on its surface, is favorable to extend the functions by introducing the spin–orbit coupling and magnetism through proximity effect. Here, we report the tunable interfacial exchange field produced by proximity coupling in graphene/BiFeO3 heterostructures. The exchange field has a notable dependence with external magnetic field, and it is much larger under negative magnetic field than that under positive magnetic field. For negative external magnetic field, interfacial exchange coupling gives rise to evident spin splitting for N ≠ 0 Landau levels and a quantum Hall metal state for N = 0 Landau level. Our findings suggest graphene/BiFeO3 heterostructures are promising for spintronics.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language (up) Wos 000430155900034 Publication Date 2018-04-11
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 12.712 Times cited 9 Open Access Not_Open_Access
Notes This work was supported by National Key Research and Development Program of China (No. 2016YFA0300802) and NSFC (Nos. 11774004 and 11604004). Ministry of Science and Technology of the People's Republic of China, 2016YFA0300802 ; National Natural Science Foundation of China, 11604004 11774004 ; Approved Most recent IF: 12.712
Call Number EMAT @ lucian @c:irua:150794 Serial 4923
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Author Liao, Z.; Gauquelin, N.; Green, R.J.; Müller-Caspary, K.; Lobato, I.; Li, L.; Van Aert, S.; Verbeeck, J.; Huijben, M.; Grisolia, M.N.; Rouco, V.; El Hage, R.; Villegas, J.E.; Mercy, A.; Bibes, M.; Ghosez, P.; Sawatzky, G.A.; Rijnders, G.; Koster, G.
Title Metal–insulator-transition engineering by modulation tilt-control in perovskite nickelates for room temperature optical switching Type A1 Journal article
Year 2018 Publication America Abbreviated Journal P Natl Acad Sci Usa
Volume 115 Issue 38 Pages 9515-9520
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract In transition metal perovskites ABO3 the physical properties are largely driven by the rotations of the BO6 octahedra, which can be tuned in thin films through strain and dimensionality control. However, both approaches have fundamental and practical limitations due to discrete and indirect variations in bond angles, bond lengths and film symmetry by using commercially available substrates. Here, we introduce modulation tilt control as a new approach to tune the ground state of perovskite oxide thin films by acting explicitly on the oxygen octahedra rotation modes, i.e. directly on the bond angles. By intercalating the prototype SmNiO3 target material with a tilt-control layer, we cause the system to change the natural amplitude of a given rotation mode without affecting the interactions. In contrast to strain and dimensionality engineering, our method enables a continuous fine-tuning of the materials properties. This is achieved through two independent adjustable parameters: the nature of the tilt-control material (through its symmetry, elastic constants and oxygen rotation angles) and the relative thicknesses of the target and tilt-control materials. As a result, a magnetic and electronic phase diagram can be obtained, normally only accessible by A-site element substitution, within the single SmNiO3 compound. With this unique approach, we successfully adjusted the metal-insulator transition (MIT) to room temperature to fulfill the desired conditions for optical switching applications.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language (up) Wos 000447224900057 Publication Date 2018-09-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0027-8424 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 9.661 Times cited 50 Open Access OpenAccess
Notes We would like to acknowledge Prof. Z. Zhong for stimulated discussion. M.H., G.K. and G.R. acknowledge funding from DESCO program of the Dutch Foundation for Fundamental Research on Matter (FOM) with financial support from the Netherlands Organization for Scientific Research (NWO). This work was funded by the European Union Council under the 7th Framework Program (FP7) grant nr NMP3-LA-2010-246102 IFOX. J.V., S.V.A, N.G. and K.M.C. acknowledge funding from FWO projects G.0044.13N, G.0374.13N, G. 0368.15N, and G.0369.15N. The Qu-Ant-EM microscope was partly funded by the Hercules fund from the Flemish Government. N.G. acknowledges funding from the European Research Council under the 7th Framework Program (FP7), ERC Starting Grant 278510 VORTEX. N.G. and J.V. acknowledge financial support from the European Union under the Seventh Framework Program under a contract for an Integrated Infrastructure Initiative (Reference No. 312483- ESTEEM2). The Canadian work was supported by NSERC and the Max Planck-UBC Centre for Quantum Materials. Some experiments for this work were performed at the Canadian Light Source, which is funded by the Canada Foundation for Innovation, NSERC, the National Research Council of Canada, the Canadian Institutes of Health Research, the Government of Saskatchewan, Western Economic Diversification Canada, and the University of Saskatchewan. MB acknowledges funding from the European Research Council under the 7th Framework Program (FP7), ERC CoG grant MINT #615759. A.M. and Ph.G. were supported by the ARC project AIMED and F.R.S-FNRS PDR project HiT4FiT and acknowledge access to Céci computing facilities funded by F.R.S-FNRS (Grant No 2.5020.1), Tier-1 supercomputer of the Fédération Wallonie-Bruxelles funded by the Walloon Region (Grant No 1117545) and HPC resources from the PRACE project Megapasta. Approved Most recent IF: 9.661
Call Number EMAT @ emat @c:irua:154784UA @ admin @ c:irua:154784 Serial 5059
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Author Yan, Y.; Zhou, X.; Jin, H.; Li, C.-Z.; Ke, X.; Van Tendeloo, G.; Liu, K.; Yu, D.; Dressel, M.; Liao, Z.-M.
Title Surface-Facet-Dependent Phonon Deformation Potential in Individual Strained Topological Insulator Bi2Se3 Nanoribbons Type A1 Journal article
Year 2015 Publication ACS nano Abbreviated Journal Acs Nano
Volume 9 Issue 9 Pages 10244-10251
Keywords A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT)
Abstract Strain is an important method to tune the properties of topological insulators. For example, compressive strain can induce superconductivity in Bi2Se3 bulk material. Topological insulator nanostructures are the superior candidates to utilize the unique surface states due to the large surface to volume ratio. Therefore, it is highly desirable to monitor the local strain effects in individual topological insulator nanostructures. Here, we report the systematical micro-Raman spectra of single strained Bi2Se3 nanoribbons with different thicknesses and different surface facets, where four optical modes are resolved in both Stokes and anti-Stokes Raman spectral lines. A striking anisotropy of the strain dependence is observed in the phonon frequency of strained Bi2Se3 nanoribbons grown along the ⟨112̅0⟩ direction. The frequencies of the in-plane Eg2 and out-of-plane A1g1 modes exhibit a nearly linear blue-shift against bending strain when the nanoribbon is bent along the ⟨112̅0⟩ direction with the curved {0001} surface. In this case, the phonon deformation potential of the Eg2 phonon for 100 nm-thick Bi2Se3 nanoribbon is up to 0.94 cm–1/%, which is twice of that in Bi2Se3 bulk material (0.52 cm–1/%). Our results may be valuable for the strain modulation of individual topological insulator nanostructures.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language (up) English Wos 000363915300079 Publication Date 2015-09-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1936-0851;1936-086X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 13.942 Times cited 14 Open Access
Notes Y.Y. would like to thank Xuewen Fu for helpful discussions. This work was supported by MOST (Nos. 2013CB934600, 2013CB932602) and NSFC (Nos. 11274014, 11234001). Approved Most recent IF: 13.942; 2015 IF: 12.881
Call Number c:irua:129216 Serial 3963
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Author Liao, Z.; Huijben, M.; Zhong, Z.; Gauquelin, N.; Macke, S.; Green, R.J.; Van Aert, S.; Verbeeck, J.; Van Tendeloo, G.; Held, K.; Sawatzky, G.A.; Koster, G.; Rijnders, G.
Title Controlled lateral anisotropy in correlated manganite heterostructures by interface-engineered oxygen octahedral coupling Type A1 Journal article
Year 2016 Publication Nature materials Abbreviated Journal Nat Mater
Volume 15 Issue 15 Pages 425-431
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Controlled in-plane rotation of the magnetic easy axis in manganite heterostructures by tailoring the interface oxygen network could allow the development of correlated oxide-based magnetic tunnelling junctions with non-collinear magnetization, with possible practical applications as miniaturized high-switching-speed magnetic random access memory (MRAM) devices. Here, we demonstrate how to manipulate magnetic and electronic anisotropic properties in manganite heterostructures by engineering the oxygen network on the unit-cell level. The strong oxygen octahedral coupling is found to transfer the octahedral rotation, present in the NdGaO3 (NGO) substrate, to the La2/3Sr1/3MnO3 (LSMO) film in the interface region. This causes an unexpected realignment of the magnetic easy axis along the short axis of the LSMO unit cell as well as the presence of a giant anisotropic transport in these ultrathin LSMO films. As a result we possess control of the lateral magnetic and electronic anisotropies by atomic-scale design of the oxygen octahedral rotation.
Address MESA+ Institute for Nanotechnology, University of Twente, PO Box 217, 7500 AE Enschede, The Netherlands
Corporate Author Thesis
Publisher Place of Publication Editor
Language (up) English Wos 000372591700017 Publication Date 2016-03-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1476-1122 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 39.737 Times cited 273 Open Access
Notes We would like to acknowledge Dr. Evert Houwman for stimulated discussion. M.H., G.K. and G.R. acknowledge funding from DESCO program of the Dutch Foundation for Fundamental Research on Matter (FOM) with financial support from the Netherlands Organization for Scientific Research (NWO). This work was funded by the European Union Council under the 7th Framework Program (FP7) grant nr NMP3-LA-2010- 246102 IFOX. J.V. and S.V.A. acknowledges funding from FWO project G.0044.13N and G. 0368.15N. The Qu-Ant-EM microscope was partly funded by the Hercules fund from the Flemish Government. N.G. acknowledges funding from the European Research Council under the 7th Framework Program (FP7), ERC Starting Grant 278510 VORTEX. N.G., S.V.A., J.V. and G.V.T. acknowledge financial support from the European Union under the Seventh Framework Program under a contract for an Integrated Infrastructure Initiative (Reference No. 312483-ESTEEM2). The Canadian work was supported by NSERC and the Max Planck-UBC Centre for Quantum Materials. Some experiments for this work were performed at the Canadian Light Source, which is funded by the Canada Foundation for Innovation, NSERC, the National Research Council of Canada, the Canadian Institutes of Health Research, the Government of Saskatchewan, Western Economic Diversification Canada, and the University of Saskatchewan. Z.Z. acknowledges funding from the SFB ViCoM (Austrian Science Fund project ID F4103- N13), and Calculations have been done on the Vienna Scientific Cluster (VSC).; esteem2jra2; esteem2jra3 ECASJO_; Approved Most recent IF: 39.737
Call Number c:irua:133190 c:irua:133190UA @ admin @ c:irua:133190 Serial 4041
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