Propagation characteristics of magnetoelastic surface waves in magnetic layer on non-piezoelectric substrate

The propagation characteristics of magnetoelastic surface waves in a magnetic layer on a nonpiezoelectric substrate are analyzed taking account of both thicknesses of the magnetic layer and the substrate Three fundamental modes of waves propagate in this layered structure; the extensional and the flexural modes of (P+SV)-wave and SH-wave. In these waves, the largest velocity change with external applied field appears in the flexural mode of (P+SV)-wave. The analysis reveals that the maximum velocity change has approximate squared dependence of the ratio of the magnetic layer thickness to the substrate thickness. In addition, in order to obtain large velocity change, magnetic materials are required to possess two extreme magnetic properties at the same time - very soft magnetism and very high magnetostriction.