Electronic‐Structure Control of Ferromagnetism in Fe 3 GeTe 2 and Fe 3 GaTe 2 : A Short Review

Metallic van der Waals magnets provide an unusually direct setting in which electronic structure, dimensionality, and magnetic order can be tuned within the same crystalline platform. Fe 3 GeTe 2 is a benchmark itinerant van der Waals ferromagnet because its Curie temperature, perpendicular magnetic anisotropy, coercivity, and anomalous Hall response depend strongly on thickness, stoichiometry, electrostatic gating, and interlayer hybridization. Above‐room‐temperature ferromagnetism in the structurally related Fe 3 GaTe 2 raises a central question: does Ga substitution act mainly through carrier doping, or does it produce a broader reconstruction of bonding, exchange, anisotropy, and defect chemistry? This Short Review compares Fe 3 GeTe 2 and Fe 3 GaTe 2 from the perspective of carrier and band‐structure control. Evidence from gating, photoemission, magnetotransport, magnetic imaging, quantum sensing, scalable growth, and first‐principles theory demonstrates that Fe‐derived states near the Fermi level are highly tunable and that modest electronic changes can produce large magnetic responses. However, the comparison cannot be reduced to a rigid‐band picture. Ga changes the nominal electron count while also modifying orbital hybridization, lattice geometry, magnetic anisotropy, and defect formation. The enhanced Curie temperature of Fe 3 GaTe 2 is therefore interpreted as the result of coupled electronic and structural optimization, suggesting practical design principles for high‐temperature metallic van der Waals magnets.