Nonlinear Microwave Phenomena in Ferrite Films : Basic Physics and Applications (Invited)

A short overview of the theory and applications of nonlinear spin wave phenomena in ferrite films at microwave frequencies is given. A method of classical Hamiltonian formalism for spin waves in bulk femmagnets in combination with the theory of spin wave spectrum for thin magnetic films is used for theoretical description of nonlinear spin wave phenomena in films. Comparative roles of three-wave and four-wave interaction processes in the nonlinear dynamics of spin waves in films are discussed. A local character of spin wave excitation by the magnetic field of a strip-line antenna is taken into account. Several examples of nonlinear microwave signal processing devices based on the nonlinear dynamics of spin waves in ferrite films (frequency-selective limiter, signal-to-noise enhancer, convolver , and a soliton delay line) are presented.