Photothermoacoustic effect in solids with piezoelectric detection

The photothermoacoustic effect in solids with piezoelectric signal detection is investigated theoretically and experimentally. Analytical expressions are found for the amplitude and phase shift of the photothermoacoustic signal as a function of the thicknesses of the sample and piezoelectric transducer, the modulation frequency, and the material constants of the structure. A method is proposed for detecting the signal using a compound piezoelectric transducer. It is shown for a bilayer piezoelectric transducer that the reduced Young’s modulus and the thermal diffusion coefficient of the experimental object can be found from the amplitude-frequency and phase-frequency curves. Zh. Tekh. Fiz. 69, 1–5 (December 1999)