Toward Two-Dimensional Dirac Half-metallic MX3 for Spintronics

The development of two-dimensional (2D) materials with the coexistence of intrinsic half-metallic and Dirac features will be of great realistic significance for next-generation spintronic nano-devices. Using first-principles calculations, we demonstrate that the pristine 2D MX₃ are the highly desired Dirac half metals and feasible in experiment. All MX₃ monolayers possess Dirac cone in the conducting spin channel with high Fermi velocities, while the other spin orientations have large energy gaps. The evaluated Curie temperature indicate MX₃ monolayers can maintain their ferromagnetism beyond room temperature. Remarkably, our results show that some monolayers exhibit large magnetocrystalline anisotropy (MCA). When including the spin−orbit coupling, the Dirac cones open small gaps and give rise to topologically nontrivial states with nonzero Chern number (-1), indicating MX₃ MLs are the Chern insulator and Chern half-metals. This work not only highlight the promising candidates for future spintronic applications, but also paves the way for the realization of integrating the long-craved qualities and quantum anomalous Hall effect (QAHE) in pristine 2D layers.