Propagation of Rayleigh waves in a phononic crystal with one-dimensional periodic-polarization layer

We investigate theoretically the propagation of Rayleigh wave in one-dimensional elastic substrate with a periodic-polarization lithium niobate (LiNbO
₃
) layer. The first band gap of Rayleigh wave is calculated by plane wave expansion (PWE) method and finite element method (FEM). The effects of the waveguide layer on the band gap is analyzed. Numerical analysis shows that the thickness of the layer has a significant effect on the first band gap. From the result, we can find that the filling fraction can influence the width of the band gap. The transmission of the Rayleigh wave through finite element is also given.