Numerical characterization of piezoelectric resonant transducer modes for acoustic wave excitation in optical fibers

The control of light in optical fibers by acoustic waves often requires a piezoelectric transducer as acoustic driver. As the fiber acoustic excitation depends on the deformation and frequency of the transducer, the analysis of the resonances and piezo mechanical behavior provides more efficient operation for acousto-optic devices. In this paper, an acousto-optic modulator is modeled using a three-dimensional finite element method in order to investigate the effect of the vibration modes of a piezoelectric disc in the excitation of acoustic waves in a fiber segment. The results indicate that in specific resonances, transducer radial and thickness modes are useful for the excitation of flexural and longitudinal acoustic waves in optical fiber.