Anti-plane shear wave motion in a composite layered structure with slit

Anti-plane shear wave propagation in a functionally graded piezoelectric substrate and a piezoelectric substrate guided by a slit is analyzed theoretically. The equations of motion are taken from the linear theory of piezoelectricity for polarized ceramics. The dispersion relation is obtained by applying appropriate boundary conditions on the derived solutions. PZT-5 and ZnO are taken as numerical examples to manifest the effect of different material parameters (gradient factor, slit width etc.) graphically on the phase and group velocity of the considered wave. LiIO3 and BaTiO3 materials are taken separately to compare the results. Also, graphs are plotted for different modes of the wave as well as for different frequency ranges and for the case when slit is absent. As a special case, it is remarked that the present study has resemblance with one of the existing works. The highlights of the study are to characterize the anti-plane wave propagation within a functionally graded piezoelectric sub-strate/gap/piezoelectric substrate coupled structure, to show the effect of different parameters, modes, frequency, etc. on the velocity profile of the considered wave and to show the effect of gap layer. The outcomes of this study may be used to enhance the sensitivity of acoustic wave devices and sensors.