Abstract
We propose that the van der Waals layered ternary transition metal chalcogenides FeTaX₂ (X= S, Se, Te) as a new family of ferrimagnetic quantum anomalous Hall insulators with a sizable bulk gap and high Chern number C=-2. The magnetic order arises primarily from Fe atoms, whose strong ferromagnetic exchange induces moments on neighboring Ta sites. The large topological gap originates from a \emph{deep} s-d-type band inversion between spin-down Ta d_z² and d_xy orbitals near the Fermi level-a mechanism unique to d-orbital systems. Remarkably, the Curie temperature of monolayer FeTaX₂ is predicted to significantly exceed that of monolayer MnBi₂Te₄. Furthermore, both the Curie temperature and topological gap scale positively with the spin-orbit coupling strength of the d electrons, suggesting a common physical origin. Owing to its structural similarity to FeX superconductors and reduced net magnetization, FeTaX₂ further offers a promising platform for realizing chiral topological superconductivity. These findings, if realized experimentally, could open new avenues for the research and application of topological quantum physics.