Magnetic Skyrmions in CrGaTe3 Monolayer

Two-dimensional (2D) magnetic skyrmions hold great promise for next-generation high-density information storage, yet their low-dimensional behavior and controllable size remain challenging. Here, combining first-principles calculations and Monte Carlo simulations, we identify monolayer CrGaTe3, derived from the Ga2S3 structure, as a ferromagnetic half-metal and a robust platform for hosting topological spin textures. The system exhibits a substantial Dzyaloshinskii−Moriya interaction (DMI) of 2.36 m V, arising from intrinsic inversion asymmetry and strong spin−orbit coupling, alongside sizable Kitaev exchange and magnetic anisotropy. At zero field, the ground state adopts a Néel-type cycloid state, which evolves into stable skyrmion phases under moderate external magnetic fields. Remarkably, beyond field tuning, we find that biaxial strain not only modulates the skyrmion size but also induces skyrmion states under tensile conditions, offering an additional degree of freedom for topological phase engineering. Furthermore, our parameter-resolved analysis reveals that while DMI is pivotal for skyrmion nucleation, the Kitaev interaction and magnetic anisotropy collectively govern the size and density of the skyrmion lattice. These findings establish monolayer CrGaTe3 as a promising candidate for sub-10 nm spintronic devices and demonstrate that the synergy between intrinsic symmetry breaking and external stimuli provides a generalizable strategy for designing functional 2D magnets.