THEORY OF INTERACTION OF LIGHT WITH AN INTENSIVE SPIN-WAVE IN A FERROMAGNETIC FILM

The peculiarities of a strong collinear magneto-optical interaction of guided light with an intensive spin wave (SW) undergoing modulational instability have been studied. To quantify these effects, which accom pany the optical diffraction, a numerical technique based on a perturb ation approach has been developed. Extensive numerical simulations of the magneto-optical diffraction by SW affected by nonlinear automodula tion were carried out. The parameters of interaction related to automo dulation mechanisms were varied within a wide range of values, coverin g most situations of practical interest. It has been shown that the in crease in the modulation frequency F minimizes nonlinear distortions i n the output optical spectrum, and for F>60 MHz the level of second ha rmonic in the diffraction spectrum declines below -60 dB.