Acoustic-mode analysis of a homogeneous multilayer guiding structure

Abstract

A generalized acoustic-mode dispersion analysis of a multilayer guiding structure that includes a combination of homogeneous layers of materials with well-defined mechanical and piezoelectric properties is developed. A few examples are also presented that are relevant to a simple bulk LiNbO3 structure and to ZnO/GaAs and ZnO/GaAs/AlGaAs/GaAs composite structures. In particular, a surface acoustic-wave velocity of 3734 m/sec is calculated for a Y-cut LiNbO3 monolayer, 1.4 μm thick, at an acoustic frequency of f = 650 MHz, which is in good agreement with the value in the literature, the difference being less than 1%.