NONLINEAR SELF-LOCALIZED DIPOLE-EXCHANGE SURFACE SPIN-WAVES ON FERROMAGNETIC MEDIA

A type of self-localized, surface, dipole-exchange spin wave on a ferr omagnet is predicted, the existence of which is controlled entirely by the nonlinear properties of the ferromagnetic medium. Dispersion equa tions have been obtained for dipole-exchange nonlinear spin waves and the influence of second-harmonic generation on the wave, propagating a t the fundamental frequency, is investigated. The nonlinear Schrodinge r equation, for the spin-wave envelope amplitude, is derived and its s olitonic solutions are discussed. Estimates of the threshold values of the wave numbers of the propagating waves are obtained.