Some properties of ferrite-filled circular waveguide

The paper describes the propagation behaviour of a circular wave-guide filled with a longitudinally magnetized ferrite. It is shown that, in a certain range of applied magnetic field and frequency, a slow backward wave can propagate. The dependence of the propagation coefficient of this mode on magnetic and dimensional parameters is determined. Experimental evidence in support of the theory is given, and possible applications of the phenomena to backward-wave tubes and filters are discussed.