MSFVW dispersion control utilizing a layered YIG-film structure

This paper reports a theoretical study of the dispersion control of MSFVWs that is afforded by the use of a double-layered YIG film produced by growing a second film with a different saturation magnetization on top of the first film. In particular, the effect of the presence of the second YIG film on the MSFVW nondispersive propagation obtaining in a single-YIG-film/dielectric/ground-plane structure is examined. It is found that, with the ground plane sufficiently spaced from the layered YIG film so that the conductive loss is small, a significant improvement in bandwidth for MSFVW nondispersive propagation over a single-film structure is obtained if the YIG film closer to the ground plane has the higher saturation magnetization of the two films.