Control of time structure for acoustic pulses at parametric phase conjugation of acoustic beams

Abstract

The feasibility of controlling the time profile of a periodic sequence of acoustic pulses is studied within the framework of a general phenomenological description. The control is implemented for the case of a parametric spatial phase conjugation of a beam under the conditions of pulsed modulation of sound velocity in a phase-conjugating system. General expressions for the amplitudes and phases of equidistant spectral components of a phase-conjugate sound wave are obtained depending on the Fourier spectrum of the pumping field in the phase-conjugating medium. The time dependence of the profile of the phase-conjugate sound wave on the form of pumping is studied on this basis under different conditions, including the mismatch of the carrier frequencies of pumping and acoustic field.