Power flow in magnetoelastic media

Abstract
A Lagrangian formulation is used to obtain an expression for the power flow in a magnetoelastic wave in the presence of the exchange interaction and of damping in the system. The result is illustrated by a calculation of the time average of the power flow in a bulk shear wave, in a bulk magnetoelastic wave, and the total power flow, per unit width of the beam, in a shear-polarized magnetoelastic surface wave propagating perpendicular to the magnetization.