CHUCHMAN M. Emissive characteristics and physics of processes in laser plasma of gallium, indium, lead, antimony and compounds on their basis

The dissertation presents the results of the first systematic researches of emissive characteristics and parameters of laser erosive plasma of CuInS2, CuSbS2, AgGaS2, PbGa2S4 compounds as well as their components with the action of pulse-periodic infrared radiation of neodymium laser on a target. Laser pulse is characterised by nanoseconds duration and 108-109 W/cm2 power density. It is established that the plasma radiates due to radiating relaxation of one- and two-electronic excited states of atoms and one-charged ions. The analysis of spectra and dynamics of the radiation of laser plasma for compounds and their components has allowed to refer the specificity of behaviour of such plasma on distance of 1 mm from a target to strong influence on process of laser erosion of a method of input of energy and kind of energy which partiсles exchange. The characteristic feature of ion formation by laser erosion of multicomponent targets is ionization and dissociation of compound molecules. These proсess are run by different mechanisms at different stages of erosion. The motion speed of plasma, the recombination time of ions, the temperature and density of electrons were determined. With expansion to 7 mm the heterogeneity of space composition and parameters gradually smoothes out by intermixing of plasma. The main mechanism of excitation is recombination. Key words: laser erosive plasma, spectra and dynamics of radiation, electron temperature and density.