Properties of Pt-supported Co nanomagnets from relativistic density functional theory calculations

The electronic, structural, and magnetic properties of Co-based low-dimensional nanostructures supported by Pt surfaces are investigated using computer simulations based on density functional theory. The effects of the local orientation of the magnetization, including the magnetic anisotropy energy, are accounted for within a noncollinear spin-density functional theory formalism where the spin-orbit interaction is described by fully relativistic ultrasoft pseudopotentials. The magnetic moments, the direction of the easy-magnetization axis, and the anisotropy energy are compared with available experimental and theoretical data, and are shown to be extremely sensitive to the local atomic environment of the Co adatoms. We argue that this sensitivity could be exploited to tailor the properties of magnetic devices by engineering the local environment and/or the operating conditions of nanomagnets.