Characterization of magnetostatic wave devices by Brillouin light scattering

Brillouin light scattering (BLS) has been used for direct detection of backward volume wave (BVW) excitations in yttrium iron garnet (YIG) films in magnetostatic wave devices. The measurements were carried out on delay line structures and on a signal-to-noise enhancer device. With an applied field parallel to the film plane and perpendicular to the stripline, backward volume waves are excited in the YIG film by the stripline power. Using the BLS technique, the BVW excitations in the YIG film were observed over the frequency range 2-4 GHz. The observed BVW band limits are in reasonable agreement with theory. There is very good agreement between the experimental and the theoretical dispersion for the BVW excitations. The scattering was found to be rather weak over the BVW passband, but did reveal considerable structure.