Ultra-thin ferromagnets with large magnetic anisotropy by assembling MnCl3 superatoms on SbAs monolayer

Two-dimensional (2D) magnetic materials with large magnetic anisotropy are crucial for developing thermally stable, miniaturized, and low-power spintronic devices. However, naturally existing 2D materials with intrinsic anisotropic magnetization are scarce. Employing a bottom-up primitive assembly approach and first-principles calculations, we find that the adsorption of MnCl ₃ superatoms not only induces magnetism in non-magnetic monolayer SbAs but also hardens it (large out-of-plane magnetic anisotropy). The MnCl ₃/SbAs system becomes a ferromagnetic half-metal with high Curie temperature. Interestingly, the delocalized p orbitals of Sb/As not only mediate the long-range magnetic exchange but also contribute to the significant magnetic anisotropic energy. The magnetic exchange and anisotropy of the system can be efficiently modulated by changing the assembly mode of MnCl ₃ on the SbAs surface. This study presents an alternative concept and method for the development of 2D ferromagnetic materials with uniaxial magnetic anisotropy, which holds promise for spintronic device applications.