Two types of magnetic shape-memory effects in Fe<sub>1+y</sub>Te

ORAL

Abstract

The discovery of superconductivity in β-FeSe triggered considerable interest also in the related tellurium compound Fe1+yTe. Here we present a detailed experimental study of Fe1+yTe (y = 0.11 and 0.12) using pulsed magnetic fields up to 60 T. Our studies confirmed two types of magnetic shape memory (MSM) effects in the low temperature antiferromagnetic state of these compounds [1]. Scanning tunneling microscopy measurements at low temperature established a modulated and finely twinned martensitic microstructure. The antiferromagnetism of the monoclinic phase allows for a magnetic–field–induced reorientation of these twin variants by the motion of twin boundaries. At sufficiently high magnetic fields, we observed a second isothermal transformation process. This gives rise to a second MSM effect caused by a phase transition back to the field-polarized tetragonal lattice state [2]. Observation of MSM effects in two known material families [1,3] related to high-Tc superconductors points to a prominent role of electron–phonon coupling arising through the spin–orbit interactions.
[1] S. Rößler et al., Proc. Natl. Acad. Sci. USA, 116, 16697 (2019).
[2] X. Fabreges et al., Phys. Rev. B 95, 174434 (2017).
[3] A. N. Lavrov et al., Nature 418, 385 (2002).

–

Presenters

  • Sahana Roessler

    • Max Planck Institute for Chemical Physics of Solids, Dresden, Germany
    • Max Planck Institute for Chemical Physics of Solids, Dresden, Germany.

Authors

  • Sahana Roessler

    • Max Planck Institute for Chemical Physics of Solids, Dresden, Germany
    • Max Planck Institute for Chemical Physics of Solids, Dresden, Germany.

  • Cevriye Koz

    • Max Planck Institute for Chemical Physics of Solids, Dresden, Germany

  • Zhaosheng Wang

    • High Magnetic Field Laboratory, Chinese Academy of Sciences, People’s Republic of China

  • Yurii Skourski

    • Helmholtz-Zentrum Dresden-Rossendorf, Germany

  • Mathias Doerr

    • Institute of Solid State and Materials Physics, Technical University, Dresden, Germany

  • Deepa Kasinathan

    • Max Planck Institute for Chemical Physics of Solids, Dresden, Germany

  • Helge Rosner

    • Max Planck Institute for Chemical Physics of Solids, Dresden, Germany
    • Max Planck Institute for Chemical Physics of Solids

  • Marcus Schmidt

    • Max Planck Institute for Chemical Physics of Solids, Dresden, Germany

  • Ulrich Schwarz

    • Max Planck Institute for Chemical Physics of Solids, Dresden, Germany

  • Ulrich Roessler

    • IFW Dresden
    • Institute for Theoretical Solid State Physics, IFW Dresden, Germany
    • IFW Dresden, Leibniz-Institut fur Festkorper- und Werkstoffforschung

  • Steffen Wirth

    • Max Planck Institute for Chemical Physics of Solids, Dresden, Germany