Spectroscopic signature of 3D magnetism in the itinerant van der Waals ferromagnet Fe<sub>5</sub>GeTe<sub>2</sub>

ORAL

Abstract

Recently discovered family of high-temperature itinerant van der Waals ferromagnets Fe5-xGeTe2. Moreover, Fe5GeTe2 displays the highest Tc ~ 315 K and has the potential for magnonic devices operating at room temperature [4,5]. However, it is not yet known whether magnons in Fe5GeTe2 are confined to 2D or propagate in 3D. Investigation of dispersing magnons via inelastic neutron scattering is not feasible due to the small size of available single crystals. In this study, we overcome this issue by employing a complimentary probe, resonant inelastic x-ray scattering (RIXS), on a high-quality mm-size single crystal of Fe5GeTe2 [5]. A broad magnetic continuum stretching up to 150 meV and displaying a strong intensity modulation along (00L) is observed [6]. We show that this intensity modulation is compatible with a dominant inter-slab magnetic interaction enabling 3D propagation of magnons in the room-temperature ferromagnet Fe5GeTe2 [6].

1. Y. Zhang, et al., Sci. Adv. 4, eaao6791 (2018).

2. X. Wu, et al., Phys. Rev. B 104, 165101 (2021).

3. K. Yamagami, et al., Phys. Rev. B 106, 045137 (2022).

4. L. Alahmed, et al., 2D Mat 8, 045030 (2021).

5. A. May, et al., ACS Nano 13, 4436 (2019).

6. V. K. Bhartiya, et al., unpublished.

*This work was primarily supported by the U.S. Department of Energy (DOE), Office of Science, Basic Energy Sciences, Early Career Award Program (Brookhaven National Laboratory). This research used beamline 2-ID of the National Synchrotron Light Source II, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Brookhaven National Laboratory under Contract No. DE-SC0012704.

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Publication: V. K. Bhartiya, et al., unpublished.

Presenters

  • Vivek Bhartiya

    • Brookhaven National Laboratory

Authors

  • Vivek Bhartiya

    • Brookhaven National Laboratory

  • Jiemin Li

    • Brookhaven National Laboratory
    • NSLS II, Brookhaven National Lab

  • Yanhong Gu

    • NSLS II, Brookhaven National Lab
    • BNL
    • Brookhaven National Laboratory

  • Taehun Kim

    • Brookhaven National Laboratory

  • Shiyu Fan

    • Brookhaven National Laboratory
    • National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, New York 11973, USA

  • Xiaodong Xu

    • University of Washington

  • Dmitri N Basov

    • Columbia University
    • Department of Physics, Columbia University, New York, NY, USA

  • Jonathan Pelliciari

    • Brookhaven National Laboratory
    • NSLS II, Brookhaven National Lab

  • Andrew F May

    • Oak Ridge National Lab
    • Oak Ridge National Laboratory

  • Valentina Bisogni

    • Brookhaven National Laboratory
    • NSLS II, Brookhaven National Lab