Acoustic Radiation from Ends of IDT in Synchronous LSAW Resonators

In order to minimize losses due to bulk-acoustic radiation, ‘leaky’ SAW resonators on rotated Y-cut LiTaO3 typically employ synchronous design, with all the electrodes in the IDT and in the reflectors sharing the same periodicity and electrode shape. The change in the electric connection pattern between the IDT and the reflectors creates an electric discontinuity, which can serve as an additional source of bulk wave radiation.

In this work, numerical FEM simulations are employed to characterize this additional loss mechanism.