Presence of Stark ladders in scattering of shear horizontal piezoelectric waves

The global matrix techniques are used in the analysis of the Stark-Ladder resonances for transverse horizontal and surface waves in piezoelectric multilayers. Stark-Ladder resonances are observed when these waves propagate inside composites consisting of N piezoelectric layers whose piezoelectric properties obey a special linear relation. Each layer is made of materials with hexagonal 6 mm symmetry. The resonances are studied through the transmission coefficient. The transmission coefficient shows the well known band structure for a periodic piezocomposite, and when a linear term in the values of the piezoelectric parameters of the layers (which breaks the periodicity) is added, the band structure is destroyed and, in certain cases, resonances of the Stark-Ladder type are shown. The transmission coefficient is studied as a function of the properties of the materials and angle of incidence of the waves. Numerical results for two different configurations of piezocomposites are presented, one of them showing the existence of Stark-Ladders resonances. An analysis of the resonance spectrum is given. (C) 2004 American Institute of Physics.