Magnetocrystalline anisotropy

From Wikipedia, the free encyclopedia

It has been suggested that this article or section be merged into Magnetic anisotropy. (Discuss)

Magnetocrystalline anisotropy is the energy cost per atom to align its magnetization from one crystallographic direction to another. It is a special case of magnetic anisotropy. The spin-orbit interaction is the primary source of the magnetocrystalline anisotropy.

The direction of a magnetization relative to body that supports it is determined mainly by two effects, shape anisotropy and magnetocrystalline anisotropy. The first arises from magnetostatic effects and the second from spin-orbit coupling between the spins and the lattice of the material. The magnetostatic effects can be worked out from micromagnetic calculations, but the magnetocrystalline anisotropy must be computed from the electronic structure of the material. This is an important quantity because it determines whether a magnetic material can be made into a good hard magnet, a good soft magnet or neither. Hard magnets are an essential component of electromagnetic motors and soft magnets are an essential component of transformers.