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Abstract Recent developments in 2D magnetic materials have motivated the search for new van der Waals magnetic materials, especially Ising‐type magnets with strong magnetic anisotropy. Fe‐basedMPX3(M= transition metal,X= chalcogen) compounds such as FePS3and FePSe3both exhibit an Ising‐type magnetic order, but FePSe3receives much less attention compared to FePS3. This work focuses on establishing the strategy to engineer magnetic anisotropy and exchange interactions in this less‐explored compound. Through chalcogen and metal substitutions, the magnetic anisotropy is found to be immune against S substitution for Se whereas tunable only with heavy Mn substitution for Fe. In particular, Mn substitution leads to a continuous rotation of magnetic moments from the out‐of‐plane direction toward the in‐plane. Furthermore, the magnetic ordering temperature displays non‐monotonic doping dependence for both chalcogen and metal substitutions but due to different mechanisms. These findings provide deeper insight into the Ising‐type magnetism in this important van der Waals material, shedding light on the study of other Ising‐type magnetic systems as well as discovering novel 2D magnets for potential applications in spintronics.
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This content will become publicly available on July 25, 2027
Giant Exfoliation Induced Magnetic Coercivity in Fe 3 GaTe 2
ABSTRACT Permanent magnets with strong anisotropy and high coercivity underpin modern information and energy technologies, yet rare‐earth‐free alternatives remain limited. Here, we show that thickness engineering via mechanical exfoliation induces hard magnetic behavior in the van der Waals ferromagnet Fe3GaTe2. Bulk crystals exhibit Curie temperatures above 350 K but negligible room‐temperature coercivity. When thinned below ∼100 nm, the coercive field is dramatically enhanced, reaching nearly 1 T at room temperature for in‐plane fields—comparable to conventional hard magnets. Micromagnetic analysis reveals a crossover in magnetization reversal from domain‐mediated processes in bulk samples to quasi‐coherent rotation in thin flakes, driven by increased effective anisotropy and suppressed domain formation. This thickness‐dependent transition enables tuning of magnetic hardness without chemical modification. Combined with high saturation magnetization and robust room‐temperature performance, Fe3GaTe2emerges as a promising rare‐earth‐free material for spintronic applications. Its layered structure further allows integration into van der Waals heterostructures, where large in‐plane coercivity can stabilize magnetic states against perturbations and interlayer coupling, offering potential for high‐density nonvolatile memory and domain‐wall‐based devices.
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- Award ID(s):
- 2219003
- PAR ID:
- 10701933
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Advanced Electronic Materials
- ISSN:
- 2199-160X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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