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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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  • 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
E-mail: pecz.bela@energia.mta.hu

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