Non-linear magnetostatic surface waves pulse propagation in ferrite-dielectric-metal structure

Summary form only given. Non-linear properties of magnetostatic surface spin wave (MSSW) pulses in ferrite-dielectric-metal (FDM) structures have been studied experimentally. All experiments were performed with the pure YIG film separated from the metal plate by an air gap with the thickness t /spl ap/ 100/spl mu/m or t /spl ap/ 200/spl mu/m. Film parameters were: the thickness d /spl ap/ 14/spl mu/m, the width /spl omega/ = 2mm, the length l /spl ap/ 18mm, and ferromagnetic resonance line-width /spl Delta/H /spl ap/ 0.3Oe. The bias field was varied in the range 890-1100 Oe. It has been found that the MSSW with the wavelength /spl lambda/ comparable with the dielectric spacer thickness t is unstable for both self-modulation and parametric instabilities, while MSSW with /spl lambda/ < t or /spl lambda/ > t is unstable only for the last one. It was measured a pulse narrowing due to the bright soliton formation at frequencies in the "negative" slope region of the MSSW dispersion in the FDM structure. We have also found a strong influence of parametric instability on pulse propagation and, for this reason, we concluded that parametric instability and self-modulation are in competition.