Experimental Study of the Dynamics and Macrostructure of Laser-Induced High-Pressure Dust Gas-Plasma Flows

We propose and for the first time experimentally carry out a method of laser-induced generation of high-pressure dust gas-plasma flows with complex chemical and ionization composition under UV laser ablation of a polymer matrix containing the dust component. The method uses the difference in the spectral-energy threshold of laser ablation and optical properties of polymer materials and dust components in the short-wave-length region of the spectrum. We present the results of an experimental study of the dynamics and macrostructure of laser-induced high-pressure dust gas-plasma flows under UV ($\lambda_1=213$ nm, $\lambda_2=266$ nm, $\lambda_3=355$ nm) laser ablation of condensed targets based on a ($\mathrm{C}_2\mathrm{F}_4)_n$ polymer matrix with a dust component ($\mathrm{Si}\mathrm{O}_2$, $\mathrm{Al}_2\mathrm{O}_3$, $\mathrm{Ce}\mathrm{O}_2$). Using laser interferometry and shadowgraphy, we determined the spectral-energy thresholds and conditions for generating dust structures in ionized pairs of the target matrix and their spatiotemporal localization in a gas-dust flow up to spatial division of the evaporated substance of the target matrix and the dust-component cloud. We determine the lifetimes of heterophase flows as a function of the parameters of laser action on a condensed target and the charge of dust particles.