Analysis of Magneto-Surface-Acoustic-Wave Propagation Taking Account of the Micro-Eddy Current Loss

A procedure similar to that of the preceding report (TJMJ850385) is used in theoretical analysis of magneto-surface-acoustic-wave (MSAW) propagation in a conductive magnetostrictive medium on an insulating substrate, for which eddy current losses must be considered. Numerical methods were used to obtain solutions to the MSAW dispersion relation, and the bias field dependences of velocity and attenuation for the two types of MSAWs, Rayleigh- and Love-types, are presented. Maximum attenuation occurs at that field for which magnetoelastic coupling is strongest, at about 0 Oe for Rayleigh-type and 10 Oe for Love-type MSAW propagation. It is concluded that eddy currents must be reduced to enable high-performance MSAW devices.