A weighted waveguide for surface acoustic waves based on two-dimensional pizoelectric phononic crystals

This paper has proposed a weighted waveguide for surface acoustic waves (SAW) based on two-dimensional piezoelectric phononic crystals (PnCs). In order to analyze the transmission of the weighted waveguide based on PnCs, SAW delay line model was built. In the model, period boundary condition was adopted to reduce the time and memory of model cost and perfect matching layer was adopted to absorb the reflection of the waves. Three-dimensional finite element method (FEM) was used to calculate the transmission coefficients and analyze the acoustic field distribution. Results showed that the band gaps and band passes are separated in the x and y direction. Thus the weighted waveguide can prohibit the waves in one direction while permit the waves in another direction. This property of weighted waveguide can be used in the SAW devices in the future study.