Propagation characteristics of transverse surface wave in a heterogeneous layer cladded with a piezoelectric stratum and an isotropic substrate

An analytical treatment studying the propagation behavior of Love-type wave in a piezoelectric layer bonded perfectly to an isotropic heterogeneous layer overlying an unbounded isotropic homogeneous substrate has been taken into account. Debye asymptotic expansion has been employed to attain the closed-form expressions of dispersion relation for both the cases of electrically open condition and electrically short condition. The significant impact of various affecting parameters, namely, wave number, piezoelectric constant and dielectric constant of the uppermost piezoelectric layer, width ratio of the layers, and heterogeneity parameter of the intermediate isotropic layer on the phase velocity of Love-type wave, has been remarkably traced out by means of numerical computation and graphical illustrations. In addition to this, comparative study has been carried out to unfold the concealed characteristics of the problem. As a special case of the problem, it is identified that the established dispersion relation for both the cases of electrically open condition and electrically short condition is in well agreement with the classical Love wave equation.