Power flow and energy distribution of magnetostatic bulk waves—In dielectric‐layered structure

This paper presents a theoretical investigation of guided propagation of the magnetostatic bulk waves in a normally magnetized ferrite film separated from a perfect conductor by a dielectric layer. Starting from the generalized Poynting theorem for dispersive media, the expressions for time‐averaged power flow and energy density have been obtained in the magnetostatic approximation. The velocity of time‐averaged energy flow has been shown to be equal to the group velocity, which establishes the consistency of magnetostatic approximation from the energy point of view.