A simple closed form dispersion equation for shear types of surface waves propagating in periodic structures

A closed-form dispersion relation is found for shear surface acoustic waves (SAWs), namely, Bleustein-Gulyaev waves (BGWs), surface transverse waves (STWs), and leaky waves, propagating in periodic structures in the frequency range corresponding to the Bragg stopband. Changes in the spatial structure of the waves mutually reflecting on the grating as well as bulk wave scattering are considered. A comparison with numerically obtained dispersion curves for leaky waves on 36-LiTaO/sub 3/ shows good agreement.<
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