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Using the technique of laser probing, the time dependences of the transparency factor, integral glow, and of the scattered component of probing radiation for erosional laser jets of metals exposed to intense submicrosecond laser pulses have been determined. Based on the results of laser probing, a conclusion on the condensation nature of the process of formation of a liquid-droplet phase of the target-material under the given conditions of laser action has been drawn.

The scheme of a generation of ultrasound waves based on optically excited Tamm plasmon structures is proposed. It is shown that Tamm plasmon structures can provide total absorption of a laser pulse with arbitrary wavelength in a metallic layer providing the possibility of the use of an infrared semiconductor laser for the excitation of ultrasound waves. Laser pulse absorption, heat transfer and dynamical properties of the structure are modeled, and the optimal design of the structure is found. It is demonstrated that the Tamm plasmon-based photoacoustic generator can emit ultrasound waves in the frequency band up to 100 MHz with predefined frequency spectrum.

621.373.8 Methods have been developed for the formation and characterization of an ultra-dispersed silver phase in polymeric matrices, specifically in polyvinyl alcohol films. A method for laser erosion of metals in air is proposed for production of silver nanoparticles. Polyvinyl alcohol films with silver nanoparticles can be obtained by implanting the particles in aqueous solutions of the film-forming material. A complex diagnostic method is recommended for investigation of the resulting polymeric films.Keywords: laser erosion of metals, single-wave laser probing, transmission electron microscopy, absorption spectroscopy, surface plasma resonance.Introduction. Nanotechnology has so deeply invaded our lives that it is now hard to imagine producing electronics, optics, and chemicals without using nanoscale items. Many advantages of nanostructured materials are due to the specific properties that they acquire upon reaching the dimensions (even if in one direction) of the order of tens of nanometers.Hence, the production and use of materials containing metal nanoparticles is exceedingly promising. Such metal nanoparticles exhibit a whole spectrum of properties (physical, chemical, biological) that distinguish them dramatically from bulk metals [1]. Polymeric matrices containing metal nanoparticles, in particular silver, provide an example of such a nanostructured material. The presence of a characteristic absorption band for Ag nanoparticles that is caused by a surface plasma resonance (SPR) effect enables such ultradispersed materials to be used as photoresistant optical filters.One promising method for forming Ag nanoparticles is laser erosion in air. This has been described in detail [2,3]. Herein we study the possibility of forming and investigating polymeric matrices containing embedded Ag nanoparticles that were produced by laser erosion in air under normal conditions.Experimental. Laser erosion of metals in air using submicrosecond pulses of high-power-density radiation was used to form the Ag nanoparticles. It was shown [4] that a significant number (10

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