Backward surface magnetostatic waves in the ferrite-dielectric-metal structure magnetized by a valley-type nonuniform field

Trajectories and laws of variation of the magnitude and direction of the wa ve vector of surface magnetostatic waves (MSWs) of various frequencies that propagate in the ferrite-dielectric-metal (FDM) structures magnetized by a valley-type nonuniform stationary magnetic field are investigated theoreti cally. It is shown that MSWs propagate in two channels, whose types are ide ntical to those for a ferrite firm (FF); however, the forward and backward waves (as well as the second forward wave, when it exists) can propagate in channels of both identical and different types. The forward and backward w aves transform into an extraordinary backward wave propagating in the direc tion of the forward wave; under certain conditions, an inverse transformati on may take place. An effect of the backward surface MSW (SMSW) focusing, w hich slightly depends on the thickness of the dielectric (if it does not ex ceed the thickness of ferrite), is predicted.