Envelope soliton formation length in magnetic films (abstract)

Envelope solitons of magnetostatic waves (MSW) propagating in magnetic films have recently become an object of intensive experimental and theoretical study.12 It has been shown experimentally1 that the amplitude of a fully formed envelope soliton in a weakly dissipative magnetic film decreases with propagation distance (or delay time) twice as fast as the amplitude of a sinusoidal wave in the same film. In the present paper, we report a detailed study of the process of envelope soliton formation for MSW in a high-quality, yttrium iron garnet (YIG) film. As a result of this study, we propose to define the soliton formation length L as a distance at which the doubled “solitonic” dissipation of the propagating pulse starts to manifest itself. Figure 1 shows the evolution of an input rectangular pulse (duration T=12 ns, power 1.1 W, carrier frequency 5.6 GHz of backward volume MSW propagating in a YIG film [thickness 14.6 μm, ferromagnetic resonance (FMR) linewidth 2ΔH=0.8 Oe] as a function of the propagation...