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Topological Hall Effect in Antiferromagnetic Co-Doped Fe3GaTe2
Shyam Raj Karullithodi1,2, Yeonkyu Lee3,4, Vadym Kulichenko1
1National High Magnetic Field Laboratory, Tallahassee, Florida 32310, United States.
ACS Nano
|June 18, 2026
Summary
We explored Co-doped Fe3GaTe2, discovering field-induced magnetic textures like skyrmions in the antiferromagnetic phase. This offers a platform to study skyrmion transformations and their effects on topological properties.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Magnetism
Background:
- Fe3GaTe2 is a van der Waals ferromagnet with transitions near room temperature.
- Cobalt substitution in Fe3GaTe2 induces antiferromagnetism (AFM) with a tunable Néel temperature (TN).
Purpose of the Study:
- To confirm the phase diagram of Fe3-xCoxGaTe2.
- To investigate the magnetic field-induced phenomena and topological properties in this series.
Main Methods:
- Magnetization measurements
- Electrical transport measurements
- Hall effect measurements
- Magnetic force microscopy (MFM)
Main Results:
- The phase diagram of Fe3-xCoxGaTe2 was confirmed.
- Anomalous Hall response observed due to metamagnetic transitions suppressing the AFM state.
- A significant topological Hall signal indicates field-induced chiral spin textures, potentially AFM skyrmions.
- MFM revealed magnetic domain structures consistent with chiral textures in the AFM phase.
Conclusions:
- Co-doped Fe3GaTe2 exhibits field-induced chiral spin textures, including potential AFM skyrmions.
- This material system serves as a platform for studying the transformation of AFM skyrmions to ferromagnetic (FM) skyrmions.
- Investigating these transformations can elucidate their impact on topological and skyrmion Hall effects.
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