Related Experiment Video
Updated: May 10, 2025
09:06
Visualizing Uniaxial-strain Manipulation of Antiferromagnetic Domains in Fe1+YTe Using a Spin-polarized Scanning Tunneling Microscope
Published on: March 24, 2019
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Fluctuation-driven topological Hall effect in room-temperature itinerant helimagnet Fe3Ga4
Priya R Baral1,2,3, Victor Ukleev4,5, Ivica Živković6
1Department of Applied Physics and Quantum-Phase Electronics Center, The University of Tokyo, Bunkyo-ku, Japan. baralp@g.ecc.u-tokyo.ac.jp.
Nature Communications
|April 24, 2025
Summary
A novel fluctuation-driven mechanism involving chiral magnons explains the topological Hall effect (THE) in Fe3Ga4, even without scalar spin chirality. This discovery advances the search for materials with unique topological magnetic and transport properties.
Area of Science:
- Condensed matter physics
- Materials science
- Spintronics
Background:
- The topological Hall effect (THE) signifies non-trivial spin arrangements and scalar spin chirality (SSC).
- THE is typically linked to non-coplanar magnetic structures, posing a challenge for single-k structures with zero SSC.
Purpose of the Study:
- Investigate the origin of THE in single-k magnetic structures.
- Explore the role of chiral magnons in driving THE.
- Identify novel materials exhibiting intertwined topological magnetic and transport properties.
Main Methods:
- Neutron scattering experiments to probe magnetic phases.
- Analysis of magnetic structures in monoclinic Fe3Ga4.
- Investigating the transformation of magnetic states under applied magnetic fields.
Main Results:
- Discovery of multiple nontrivial magnetic phases in Fe3Ga4.
- Observation of a helical spiral phase transforming into a transverse conical state.
- Significant THE signal detected up to and above room temperature.
Conclusions:
- A fluctuation-driven mechanism involving chiral magnons explains THE in Fe3Ga4.
- This mechanism operates in single-k magnetic structures with zero SSC.
- Fe3Ga4 is a promising material for exploring topological magnetic and transport phenomena.
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