Surface acoustic waves in 2D-phononic crystal of laminated pillars on a semi-infinite ZnO substrate

Publication date: Available online 11 September 2019Source: Physics Letters AAuthor(s): Tengjiao Jiang, Chunlei Li, Qiang HanAbstractIn this paper a phononic crystal of laminated pillars which are composed of two materials on a semi-infinite ZnO substrate is proposed. The unit cell can be regarded as a double-resonator model, which explicates the variation of band gaps. It is revealed that the band structure of the PC is highly influenced by the proportion of PZT-4 in laminated pillars. Besides, the high-frequency band gaps are the result of combined actions of the local resonance and the Bragg scattering, and the former dominates. Furthermore, the influences of the structural damping are investigated. It is observed that the bandgap-ratio remain unchanged and the band gaps translate to the right with isotropic structural loss factor increasing. Additionally, by introducing linear defects inside the laminated pillars, elastic energy at surface is strongly confined within defect pillars, and the coupling between defective pillars and SAW is governed by the physical parameter of resonators.

Source: Physics Letters A - September 13, 2019 Category: Physics Source Type: research