Abstract:

In this paper, we theoretically study the Lamb wave in a multilayered piezoelectric semiconductor (PSC) plate, where each layer is an n-type PSC with the symmetry of transverse isotropy. Based on the extended Stroh formalism and dual-variable and position (DVP) method, the general solution of the coupled fields for the Lamb wave is derived, and then the dispersion equation is obtained by the application of the boundary conditions. First, the influence of semiconducting properties on the dispersion behavior of the Lamb wave in a single-layer PSC plate is analyzed. Then, the propagation characteristics of the Lamb wave in a sandwich plate are investigated in detail. The numerical results show that the wave speed and attenuation depend on the stacking sequence, layer thickness, and initial carrier density, the Lamb wave can propagate without a cut-off frequency in both the homogeneous and multilayer PSC plates due to the semiconducting properties, and the Lamb wave without attenuation can be achieved by carefully selecting the semiconductor property in the upper and lower layers. These new features could be very helpful as theoretical guidance for the design and performance optimization of PSC devices.

Key words: piezoelectric semiconductor (PSC), Lamb wave, multilayer plate, dispersion, attenuation