Acoustically driven magnetic excitations in BAW resonators with magnetic layers

The theoretical and experimental study of a composite BAW resonator, containing layers of magnets and nonmagnetic dielectric/piezoelectric (epitaxial YIG films on GGG substrate and Al-ZnO-Al transducer), placed in bias magnetic field is presented. It is shown theoretically that due to excitations of magnetic oscillations in YIG via the magnetoelastic interaction the shift of resonance frequency in the range of intermodal distance (about 3 MHz) and Q-factor reduction of BAW resonator resonance take place. Near acoustic resonance frequency 2.5 GHz at a given effective magnetic field, corresponding to magnetoacoustic resonance, the frequency tuning in the range of ± 2 MHz was experimentally observed.