Magnetostatic volume wave propagation in multiple ferrite layers

Abstract
The dispersive charcteristics of forward and backward magnetostatic waves (MSWs) propagating in single and multiple layer yttrium iron garnet (YIG) and gallium substituted YIG films have been investigated theoretically and experimentally. The theory predicts that the multiple layer structures can support MSW modes corresponding to propagation in the individual layers as well as a composite mode linking the magnetic films. Each mode of propagation has been observed experimentally. The composite mode is excited if the film with the lower value of 4 πM is in contact with the shorted electrode transducers, while single layer modes are excited if the film sequence is reversed. The dispersion of the composite mode can be made approximately linear with proper selection of film thickness.