Nonlinear Diffraction of Magnetostatic Waves in Ferrite Films

Abstract
Two-dimensional nonlinear diffraction of magnetostatic waves (MSW) in ferrite films is studied numerically using the model of nonlinear parabolic equation. This equation is derived by a new method from a bilinear relation similar to the Lorentz lemma. It is shown, that in the framework of this model the evolution of two-dimensional backward volume MSW pulse leads to a collapse in the case of an infinite film, while in a film waveguide of a finite width the collapse can be avoided, and the pulse amplitude can be stabilized. Dynamics of modulation instability of both backward volume and forward volume MSW under continuous excitation is also investigated.