Fluctuation-driven topological Hall effect in room-temperature itinerant helimagnet Fe3Ga4
The topological Hall effect (THE) is a hallmark of a non-trivial geometric spin arrangement in a magnetic metal, originating from a finite scalar spin chirality (SSC). The associated Berry phase is often a consequence of non-coplanar magnetic structures identified by multiple k-vectors. For single - k magnetic structures however with zero SSC, the emergence of a finite topological Hall signal presents a conceptual challenge. Here, we report that a fluctuation-driven mechanism involving chiral magnons is responsible for the observed THE in a low-symmetry compound, monoclinic Fe<sub>3</sub>Ga<sub>4</sub>. Through neutron scattering experiments, we discovered several nontrivial magnetic phases in this system. In our focus is the helical spiral phase at room temperature, which transforms into a transverse conical state in applied magnetic field, supporting a significant THE signal up to and above room temperature. Our work offers a fresh perspective in the search for novel materials with intertwined topological magnetic and transport properties.
Authors
- Ivica Živković (ORCID: https://orcid.org/0000-0003-0366-8199)
- A. Stunault (ORCID: https://orcid.org/0000-0002-3123-1317)
- Victor Ukleev (ORCID: https://orcid.org/0000-0003-3703-264X)
- Youngro Lee (ORCID: https://orcid.org/0000-0002-5007-4660)
- I. I. Mazin (ORCID: https://orcid.org/0000-0001-9456-7099)
- Arnaud Magrez (ORCID: https://orcid.org/0000-0001-5933-7036)
- Y. Skourski (ORCID: https://orcid.org/0000-0002-4100-6420)
- Priya R. Baral (ORCID: https://orcid.org/0000-0002-9755-6165)
- L. Keller (ORCID: https://orcid.org/0000-0002-8492-4117)
- J. Alberto Rodríguez‐Velamazán (ORCID: https://orcid.org/0000-0002-8505-5232)
- Fabio Orlandi (ORCID: https://orcid.org/0000-0001-6333-521X)
- R. Cubitt (ORCID: https://orcid.org/0000-0003-1778-3307)
- O. Zaharko
- Pascal Manuel (ORCID: https://orcid.org/0000-0002-8845-6576)
- J. S. White (ORCID: https://orcid.org/0000-0001-7738-0150)
Institutions
- Rutherford Appleton Laboratory (GB)
- George Mason University (US)
- Helmholtz-Zentrum Berlin für Materialien und Energie (DE)
- Helmholtz-Zentrum Dresden-Rossendorf (DE)
- Paul Scherrer Institute (CH)
- Institut Laue-Langevin (FR)
- École Polytechnique Fédérale de Lausanne (CH)
- The University of Tokyo (JP)
Publication Details
- Journal
- Nature Communications
- Published
- 2025-04-24
- DOI
- https://doi.org/10.1038/s41467-025-58933-w
- Citations
- 10
- Primary Topic
- Magnetic properties of thin films
- Type
- article
- Field-Weighted Citation Impact
- 12.47
Funders
- National Science Foundation
- Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung
- Paul Scherrer Institut
- Helmholtz-Zentrum Dresden-Rossendorf
- Division of Materials Research