Ferrites At Microwave Frequencies

Includes a full mathematical treatment of the interaction of an electromagnetic wave with a gyromagnetic ferrite material.

The Use of Ferrites at Microwave Frequencies describes the applications of ferrites at microwave frequencies and the apparatus involved. Topics covered range from the properties of ferrites to gyromagnetic and non-reciprocal effects, ferrite isolators, circulators, and modulators. The use of ferrites in variable frequency filter cavities is also discussed. Mathematical explanations are reduced to the strict minimum and only the results of calculations are indicated. This book consists of seven chapters and opens with a review of the theory of magnetism, touching on subjects such as the BOHR magneton, diamagnetism and paramagnetism, ferromagnetism and antiferromagnetism, ferrimagnetism, and demagnetizing. The next chapter deals with the elementary theory of gyromagnetic effects and covers the kinetic moment theorem, precession of the spin moment, gyromagnetic resonance, complex permeability, and gyromagnetic effects in the atom. The reader is then introduced to ferrites and their properties; non-reciprocal effects and their applications; and ferrite isolators, circulators, and modulators. The final chapter describes the use of ferrites in the design of cavities whose resonant frequency is controlled by a magnetic field or filters with variable characteristics. This monograph is written primarily for microwave and electronics engineers.

Revision of a classic reference on ferrite technology Includes fundamentals as well as applications Covers new areas such as nanoferrites, new high frequency power supply materials, magnetoresistive ferrites for magnetic recording

Below is a copy of Professor Takeshi Takei's original preface that he wrote for my first book, Modem Ferrite Teclmology. I was proud to receive this preface and include it here with pride and affection. We were saddened to learn of his death at 92 on March 12, 1992. Preface It is now some 50 years since ferrites debuted as an important new category of magnetic materials. They were prized for a range of properties that had no equivalents in existing metal magnetic materials, and it was not long before full-fledged research and development efforts were underway. Today, ferrites are employed in a truly wide range of applications, and the efforts of the many men and women working in the field are yielding many highly intriguing results. New, high-performance products are appearing one after another, and it would seem we have only scratched the surface of the hidden possibilities of these fascinating materials. Dr. Alex Goldman is well qualified to talk about the state of the art in ferrites. For many years Dr. Goldman has been heavily involved in the field as director of the research and development division of Spang & Co. and other enterprises. This book, Modem Ferrite Technology, based in part on his own experiences, presents a valuable overview of the field. It is testimony to his commitment and bountiful knowledge about one oftoday's most intriguing areas of technology.