Theory of Wave Propagation in a Gyromagnetic Medium

Abstract

In recent years certain ferromagnetic materials called 
\nferrites have been commercially available and are
\n gaining increasing importance in various applications. 
\nThe chemical constitution of the ferrites is expressed by 
\nthe formula MO•Fe2O3, where M symbolizes a metal. 
\n Thus magnetite, FeO•Fe2O3, is a natural ferrite known 
\nsince antiquity, but the important step of replacing 
\nFeO by oxides of other metals was carried out but 
\nrecently and led to the development of numerous artificial ferrites.