ABSTRACT The development of van der Waals (vdW) ferromagnetic materials has triggered research toward low‐power and highly integrated 2D spintronic devices. However, practical applications are hindered by limited Curie temperature ( T c ), insufficient tunability of magnetic anisotropy, and scalability challenges. Here, wafer‐scale vdW ferromagnetic Fe 3 GaTe 2 was fabricated via molecular beam epitaxy. By precisely intralayer interstitial doping, the T c of Fe 3 GaTe 2 can be significantly enhanced from ∼380 to ∼590 K. 4D scanning transmission electron microscopy (4D‐STEM) provides direct atomic‐scale evidence for the formation of new intralayer Fe configurations. Meanwhile, this approach enables flexible manipulation of magnetic anisotropy, transitioning from perpendicular to in‐plane magnetic anisotropy with the effective magnetic anisotropy constant ( K eff ) tuned from 0.57 to −2.099 J/cm 3 . This transition in magnetic anisotropy is attributed to the reduction of magnetocrystalline anisotropy, resulting from the weakened Fe 3d orbital moments, as confirmed by x‐ray magnetic circular dichroism (XMCD). Theoretical analysis suggests that the extra intralayer Fe atoms contribute additional magnetic moments and enhanced exchange coupling, resulting in an increased T c . Our findings pave a new pathway toward 2D magnetic materials with high T c and tailored magnetic anisotropy, providing a scalable approach for room‐temperature application of vdW spintronic devices.
Zhao et al. (Sat,) studied this question.