International audienceTime resolved images of acoustic waves in the 100 MHz-2.2 GHz range are obtained for an electrically excited thin-film bulk acoustic wave resonator by means of an ultrafast optical technique. Electrical pulses, synchronized to ultrashort laser pulses, piezoelectrically excite the device, and synchronous near-infrared laser pulses interferometrically detect surface motion. The frequency dispersion is extracted using spatiotemporal Fourier transforms, revealing both longitudinal and surface acoustic modes

In this paper, we present new results on the development of piezoelectric transducers based on periodically poled ferroelectrics domains. The fabrication of test devices operating in the range 50 -500 MHz has been achieved. Pure longitudinal modes are excited, yielding high frequency operation of test devices with easily achievable lithography process (20 and 10 µm periods). The dispersion analysis of our devices is reported and the capability of the proposed waveguide to support pure longitudinal modes along the plate radial dimension is emphasized