Thermal Limits on Field Alignment of Nanoparticle FePt Media
J A. Bain, William F. Egelhoff Jr.
We derive a simple expression for the angular distribution of ferromagnetic FePt particles an applied field in thermal equilibrium. This system is closely related to the Langevin expression for paramagnetic susceptibility, which computes the average orientation of particles in this configuration. We note that practical fields are unlikely to be able to provide well-aligned arrays of the smallest thermally stable FePt particles at room temperature and that this has significant consequences for self-organized nanoparticle magnetic media. It suggests that it may be difficult to match the excellent translational order that these arrays can provide with a complementary degree of perfection in orientation for the smallest particles.
Applied Physics Letters
density data, FePt, media, nanoparticles, storage, ultra high
and Egelhoff Jr., W.
Thermal Limits on Field Alignment of Nanoparticle FePt Media, Applied Physics Letters
(Accessed March 2, 2024)