A plane-wave-expansion approach for modelling acoustic propagation in 2D and 3D piezoelectric periodic structures

Piezocomposite transducers have been developed for medical ultrasound imaging and non destructive evaluation to overcome the limitations of standard 1D probes. In the present work we propose to use an extended plane-wave-expansion (PWE) method in conjunction with the Fahmy-Adler formulation of the Christoffel problem, usually used in SAW calculations, to simulate actual 1D-and 2D-periodic piezoelectric composite devices. We are able to establish the spatial and frequency distribution of both bulk and surface acoustic waves and, in the case of an electrical excitation, to compute the mode distribution along the thickness of the plate and the harmonic admittance