Magnetostatic Wave Propagation in Yttrium-Iron-Garnet With Microfabricated Surfaces

Various periodic gratings were carved on the surface of yttrium-iron-garnet (YIG) single-crystal films by a high-precision dicing saw. The mechanical process achieved the clearer structural modification in comparison with the wet and dry processes used in the past studies. Two types of magnetostaic wave filters were prepared utilizing the YIG gratings. In a band-stop filter, the rejection notch reached 40 dB at 3 GHz. A bandpass filter possessed insertion loss of 5 dB and -3-dB bandwidth of 150 MHz. In addition, a new configuration, "apodized" grating, was proposed to eliminate the ripples in the wide-frequency range