Patterns by time diffraction grating in resonant oscillation spectrum of piezoelectric powders

Plastic deformation was induced in piezoelectric powders, whose resonant frequencies were moderately and widely spread, by applying large amplitude radio-frequency (RF) pulse sequences. The traces of them in the spectrum were described with the absolute values of the Fourier component of the applied pulses. The large amplitude oscillation brought about the change of oscillation characteristics of powders, the damping constants and the resonant oscillation frequencies. We tried to describe these results with the crystal dislocation contributions. And the readout of the changed absorption spectrum by the coherent pulses was experimentally achieved, which is expected by the inverse Fourier transformation of the resonant absorption spectrum induced.