Magnetic order in the cleavable van der Waals crystal Fe5GeTe2

ORAL

Abstract

Van der Waals bonded materials with intrinsic magnetism play a key component in several aspects of present-day materials physics. In this study, we report the structure and properties of Fe5-xGeTe2. The average crystal structure obtained from single crystal x-ray diffraction contains disorder associated with occupation of Fe/Ge split sites. Atomic-resolution STEM has been utilized to inspect the local crystal structure and has revealed local ordering. The magnetism has been characterized using magnetization measurements on single crystals, as well as powder neutron diffraction and Mössbauer spectroscopy on a polycrystalline sample. The crystals have been successfully exfoliated, and Hall effect measurements on nanoflakes confirm magnetic order near room temperature. These results demonstrate that Fe5-xGeTe2 will be a promising material for incorporation into van der Waals heterostructures and devices.

Presenters

  • Andrew May

    Materials Science & Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA, Oak Ridge National Laboratory, Materials Science and Technology Division, Oak-Ridge National Laboratory, Materials Science and Technology Division, Oak Ridge National Lab, Materials Science and Technology Division, Oak Ridge National Laboratory

Authors

  • Andrew May

    Materials Science & Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA, Oak Ridge National Laboratory, Materials Science and Technology Division, Oak-Ridge National Laboratory, Materials Science and Technology Division, Oak Ridge National Lab, Materials Science and Technology Division, Oak Ridge National Laboratory

  • Dmitry Ovchinnikov

    University of Washington

  • Qiang Zheng

    Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge National Laboratory

  • Raphael Hermann

    Oak Ridge National Laboratory, Materials Science and Technology Division, Oak Ridge National Laboratory, Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge TN-37831-6064, USA

  • Stuart Calder

    Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge National Laboratory, Neutron Scattering Division, Oak-Ridge National Laboratory

  • Bevin Huang

    University of Washington, Physics, University of Washington, Seattle

  • Zaiyao Fei

    University of Washington, Physics, University of Washington, Seattle, Department of Physics, University of Washington

  • Yaohua Liu

    Oak Ridge National Laboratory, Neutron Scattering Division, Oak Ridge National Laboratory

  • Xiaodong Xu

    University of Washington, Department of Physics, University of Washington, University of Washington, Seattle

  • Michael A McGuire

    Oak Ridge National Lab, Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge National Laboratory