Nonlinear Lorenz lemma with the influence of exchange interaction and propagation of the magnetostatic waves with higher diffraction and dispersion

An efficient method (nonlinear Lorenz lemma) for the derivation of a reduced 2D evolution equation for the nonlinear magnetostatic waves in ferrite films is developed. The method describes wave propagation in the media with spatial dispersion (caused by exchange interaction in ferrites). Higher linear and nonlinear terms are included in the evolution equation. Numerical computations show that nonlinear diffraction and dispersion affect considerably pulse propagation for sufficiently large input pulse amplitudes and distances from the input antenna.