Magnetostatic-wave propagation in media with finite electrical conductivity

The wave propagation of magnetostatic surface waves (MSSWs) is formulated in terms of the vector instead of the scalar potential theory. The present formulation of the MSSW propagation accounts for the impact of the finite conductivity of ground planes and dielectric layers and the associated losses in the film stacks. The method can handle the two-dimensional wave propagation in any plane parallel film stack. The complex dispersion equation is explicitly derived for a stack with two ground planes being located at finite distances at opposite sides from the central magnetic film. Numerical results for this configuration are presented. It is shown that the dispersion curves break up into a number of branches and that contrary to the lossless case no maxima and minima with zero group velocity occur. It is shown that the surface-wave like excitations occur within a much wider frequency band than predicted by the standard scalar theory