INTERFERENCE EFFECT IN LOVE-TYPE MAGNETO-SURFACE ACOUSTIC-WAVES

The propagation properties of Love-type magneto-surface acoustic waves (MSAW) in FeB/SiOx multilayers (0.5 mu m x 10) have been studied. The insertion loss of MSAW devices was found to vary with the applied field strength and orientation angle in an approximately periodic fashion. When the acoustic aperture was restricted to a narrow strip along the center line of a square magnetic film (1 cm x 1 cm), the oscillations of the insertion loss were greatly reduced. Calculation of the demagnetizing field showed that the resultant inhomogeneity of the internal field can produce the delay difference of the partial waves up to 1.5-2 wavelengths (lambda = 36 mu m), and cause their interference at the output transducer.