Surface acoustic wave generation in ZX-cut LiNbO3 superlattices using coplanar electrodes

We report on a configuration to generate surface acoustic waves (SAWs) in acoustic superlattices based on ZX-cut periodically poled lithium niobate. The coplanar electrode configuration allows inducing Rayleigh type SAWs with the elastic energy mainly concentrated in between the electrodes gap and under the crystal surface. With respect to standard interdigitated transducers using the same crystal orientation, the efficiency of the SAW generation in the proposed designs are similar, while, for the same grating period, the resonance frequency that can be achieved is two times larger.