Explorations on size limit of L1-FePt nanoparticles for practical magnetic storage

With the advance of HAMR technology, the storage potential of L10-FePt nanoparticles with practical considerations are of great significance. We present an L10-FePt nanoparticle model based on atomistic spin model with Langevin thermodynamics to simulate the magnetic behaviors of L10-FePt nanoparticles at Curie temperature and room temperature to explore their practical design margins. Given specific composites, the Curie temperatures of L10-FePt nanoparticles decrease with their volume sizes decrease starting from 8 nm, meaning no more laser power increment needed for smaller L10-FePt nanoparticles. However, L10-FePt nanoparticles get unstable more easily while their volume sizes decrease at room temperature within 10 years. Above all, a reasonable size of L10-FePt nanoparticles for stable information retaining should not be less than 8 nm at a certain aspect ratio.