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  • 1 Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons and Peter Grünberg Institute, D-52425 Jülich, Germany
  • 2 University of Duisburg-Essen, D-48047 Duisburg, Germany
  • 3 RIKEN Center for Emergent Matter Science (CEMS), Wako 351-0198, Japan
Open access

Magnetic skyrmions are vortex-like spin structures that are of great interest scientifically and for applications in low-power magnetic memories. The nanometer size and complex spin structure require high-resolution and quantitative experimental methods to study the physical properties of skyrmions. Here, we illustrate how Lorentz TEM and off-axis electron holography can be used to study the spin textures of magnetic skyrmions in the noncentrosymmetric B20-type helimagnet FeGe as a function of temperature and applied magnetic field. By reversing the magnetic field inside the microscope, the switching mechanism of the skyrmion lattice at 240 K is followed, showing a transition of the skyrmion lattice to the helical structure before the anti-skyrmion lattice is formed.

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  • 1.

    Kiselev NS , Bogdanov AN, Schäfer R, Rössler UK: Chiral skyrmions in thin magnetic films: new objects for magnetic storage technologies? J Phys, D Appl Phys 44, 392001 (2011)

    • Search Google Scholar
    • Export Citation
  • 2.

    Mühlbauer S , Binz B, Jonietz F, Pfleiderer C, Rosch A, Neubauer A, Georgii R, Böni P: Skyrmion lattice in a chiral magnet. Science 323, 915 (2009)

    • Search Google Scholar
    • Export Citation
  • 3.

    Yu XZ , Onose Y, Kanazawa N, Park JH, Han JH, Matsui Y, Nagaosa N, Tokura Y: Real-space observation of a twodimensional skyrmion crystal. Nature 465, 901 (2010)

    • Search Google Scholar
    • Export Citation
  • 4.

    Yu XZ , Kanazawa N, Onose Y, Kimoto K, Zhang WZ, Ishiiwata S, Matsui Y, Tokura Y: Near room temperature formation of a skyrmion crystal in thin-films of the helimagnet FeGe. Nat Mater 10, 106 (2011)

    • Search Google Scholar
    • Export Citation
  • 5.

    Shibata K , Yu XZ, Morikawa D, Kanazawa N, Kimoto K, Ishiwata S, Matsui Y, Tokura Y: Towards control of the size and helicity of skyrmions in helimagnetic alloys by spin-orbit coupling. Nat Nanotechnol 8, 723 (2013)

    • Search Google Scholar
    • Export Citation
  • 6.

    Dzyaloshinsky I : Thermodynamic theory of weak ferromagnetism in antiferromagnetic substances. J Phys Chem Solids 4, 241 (1958)

  • 7.

    Moriya T : Anisotropic superexchange interaction and weak ferromagnetism. Phys Rev 120, 91 (1960)

  • 8.

    Heinze S , von Bergmann K, Menzel M, Brede J, Kubetzka A, Wiesendanger R, Bihlmayer G, Blügel S: Spontaneous atomicscale magnetic skyrmion lattice in two dimensions. Nat Phys 7, 713 (2011)

    • Search Google Scholar
    • Export Citation
  • 9.

    Woo S , Litzius K, Krüger B, Im MY, Caretta L, Richter K, Mann M, Krone A, Reeve RM, Weigand M, Agrawal P, Lemesh I, Mawass MA, Fischer P, Kläui M, Beach GSD: Observation of room-temperature magnetic skyrmions and their current-driven dynamics in ultrathin metallic ferromagnets. Nat Mater 15, 501 (2016)

    • Search Google Scholar
    • Export Citation
  • 10.

    Kézsmárki I , Bordács S, Milde P, Neuber E, Eng LM, White JS, Rønnow HM, Dewhurst CD, Mochizuki M, Yanai K, Nakamura H, Ehlers D, Tsurkan V, Loidl A: Néel-type skyrmion lattice with confined orientation in the polar magnetic semiconductor GaV4S8. Nat Mater 14, 1116 (2015)

    • Search Google Scholar
    • Export Citation
  • 11.

    Rajeswari J , Huang P, Mancini GF, Murooka Y, Latychevskaia T, McGrouther D, Cantoni M, Baldini E, White JS, Magrez A, Giamarchi T, Rønnow HM, Carbone F: Filming the formation and fluctuation of skyrmion domains by cryo- Lorentz transmission electron microscopy. Proc Natl Acad Sci 112, 14212 (2015)

    • Search Google Scholar
    • Export Citation
  • 12.

    Shibata K , Iwasaki J, Kanazawa N, Aizawa S, Tanigaki T, Shirai M, Nakajima T, Kubota M, Kawasaki M, Park HS, Shindo D, Nagaosa N, Tokura Y: Large anisotropic deformation of skyrmions in strained crystal. Nat Nanotechnol 10, 589 (2015)

    • Search Google Scholar
    • Export Citation
  • 13.

    Du H , Che R, Kong L, Zhao X, Jin C, Wang C, Yang J, Ning W, Li R, Jin C, Chen X, Zang J, Zhang Y, Tian M: Edge mediated skyrmion chain and its collective dynamics in a confined geometry. Nat Commun 6, 8504 (2015)

    • Search Google Scholar
    • Export Citation
  • 14.

    Park HS , Yu X, Aizawa S, Tanigaki T, Akashi T, Takahashi Y, Matsuda T, Kanazawa N, Onose Y, Shindo D, Tonomura A, Tokura Y: Observation of the magnetic flux and three-dimensional structure of skyrmion lattices by electron holography. Nat Nanotechnol 9, 337 (2014)

    • Search Google Scholar
    • Export Citation
  • 15.

    Boothroyd C , Kovács A, Tillmann K: FEI Titan G2 60-300 HOLO. J Large-Scale Facil 2, A44 (2016)

  • 16.

    Saxton WO , Pitt TJ, Horner M: Digital image processing: the Semper system. Ultramicroscopy 4, 343 (1979)

  • 17.

    Morikawa D , Shibata K, Kanazawa N, Yu XZ, Tokura Y: Phys Rev B 88, 024408 (2013)

  • 18.

    Tegue MR : Deterministic phase retrieval: a Green’s function solution. J Opt Soc Am 73, 1434 (1983)

  • 19.

    Ishizuka K , Allman B: Phase measurement of atomic resolution imaging using transport of intensity equation. J Electron Microsc 54, 191 (2005)

    • Search Google Scholar
    • Export Citation
  • 20.

    Phatak C , Petford-Long AK, De Graef M: Recent advances in Lorentz microscopy. Curr Opin Solid State Mater Sci 20, 107 (2016)

  • 21.

    Cowley JM : Twenty forms of electron holography. Ultramicroscopy 41, 335 (1992)

  • 22.

    Tanigaki T , Harada K, Murakami Y, Niitsu K, Akashi T, Takahashi Y, Sugawara A, Shindo D: New trend in electron holography. J Phys, D Appl Phys 49, 244001 (2016)

    • Search Google Scholar
    • Export Citation
  • 23.

    McCartney MR , Smith DJ: Electron holography: phase imaging with nanometer resolution. Annu Rev Mater Res 37, 729 (2007)

  • 24.

    Lichte H , Lehmann M: Electron holography — basics and applications. Rep Prog Phys 71, 016102 (2008)

  • 25.

    Dunin-Borkowski RE , McCartney MR, Smith DJ: Electron holography of nanostructured materials. Encycl Nanosci Nanotechnol 3, 41 (2004)

  • 26.

    Shibata K , Kovács A, Kanazawa N, Dunin-Borkowski RE, Tokura Y: Temperature and magnetic field dependence of the internal and lattice structures of skyrmions by off-axis electron holography. submitted, arXiv:1606.05723

    • Search Google Scholar
    • Export Citation
  • 27.

    Rybakov FN , Borisov AB, Bogdanov AN: Three-dimensional skyrmion states in thin films of cubic helimagnets. Phys Rev B 87, 094424 (2013)

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  • Filippo Giannazzo - Consiglio Nazionale delle Ricerche (CNR), Institute for Microelectronics and Microsystems (IMM), Catania, Italy
  • Werner Grogger - FELMI, Graz University of Technology, Graz, Austria
  • János Lábár - Institute of Technical Physics and Materials Science, Centre for Energy Research, Hungarian Academy of Sciences, Budapest, Hungary
  • Erik Manders - Faculty of Science, SILS, University of Amsterdam, Amsterdam, The Netherlands
  • Ohad Medalia - Department of Biochemistry, Zürich University, Zürich, Switzerland
  • Rainer Pepperkok - EMBL, Heidelberg, Germany
  • Aleksander Recnik - J. Stefan Institute, Ljubljana, Slovenia
  • Sara Sandin - Division of Structural Biology & Biochemistry, School of Biological Sciences, Nanyang Technological University, Singapore
  • Nobuo Tanaka - Electron microscope Lab., Ecotopia Science Institute and Dept. of Applied Physics, Nagoya University, Japan
  • Paul Verkade - Wolfson Bioimaging Facility, Schools of Biochemistry and Physiology & Pharmacology, Biomedical Sciences Building, University of Bristol, Bristol, UK

Dr Pécz, Béla
Resolution and Discovery
Institute of Technical Physics and Materials Science
Centre for Energy Research, Hungarian Academy of Sciences
H-1525 Budapest, PO Box 49, Hungary