Study of the optoacoustic response to the laser ablation of solids by the radiation of a fiber laser under a thin layer of liquid

摘要

This paper discusses the characteristics of the optoacoustic response to the laser ablation of a steel target under a thin layer of liquid by the radiation of a pulsed fiber laser in the range of power densities 10~7-2 × 10~8 W/cm~2. The dependence of the intensity of the principal peak (5.6 kHz) of the Fourier spectrum of the optoacoustic signal on the power density of the laser radiation is determined. It is established that the character of the growth of the acoustic signal amplitude substantially depends on the properties and conditions of the appearance of a near-surface plasma.