Effect of Losses on the Group Velocity of Surface Spin Waves

Resumo

It is found that considering the dissipation of surface spin waves propagating in arbitrary directions in a magnetized ferromagnetic film results in a substantial change in the dispersion surface: it is transformed from an infinite surface into a closed and bounded one consisting of an upper part with strong attenuation and a lower part with weak attenuation that join along an inclined ellipsoidal curve. The change in the dispersion surface is shown to have a considerable effect on the directions of the group velocity of the waves.