Theory of highly anisotropic ferromagnets. III. Relationship between microscopic and macroscopic anisotropy and magnetostriction in HCP ferromagnets

For pt. II see abstr. A16937 of 1974. Magnetic anisotropy and magnetostriction of highly anisotropic HCP ferromagnets are discussed in detail. Magnon energies are expressed in terms of magnetostriction and anisotropy constants and related to the constants measured in bulk experiments. Numerical analysis removes the anomalies in the magnitude of the magnon energy gap for Dy and shows that the anisotropy constants will be strongly field dependent at zero temperature through the anisotropy of zero-point motion.