Basic Theories of Amorphous Ferrimagnets and Research on Amorphous Ferrimagnetic Insulators

Theoretical problems of amorphous ferrimagnets are discussed. Transition temperatures, compensation temperatures and thermal dependences of magnetizations in amorphous ferrimagnetic rare earth-transition metal alloys are investigated using the effective-field theory with correlations. Research on amorphous ferrimagnetic insulators is described. The results obtained suggest a new field of research in magnetism.