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Information × Registration Number 0207U004853, 0107U008294 , R & D reports Title Photonical processes into wave-guide films containing granular silver and amplification of Raman scattering of adsorbate popup.stage_title Head Ageev Leonid Opanasovich, Registration Date 03-10-2007 Organization Kharkov national university named after V.N. Karazin popup.description2 The objects of research are photoinduced effects occurring in granular silver films on quartz or glass substrates irradiated by either laser or incoherent light, and in waveguide films precipitated on the substrates. The purpose of project is theoretical and experimental research of nanostructured layers which may be used to amplify giant Raman scattering. The methods of research are the following: thin film deposition on transparent plane-parallel plates by thermal evaporation of a substance in vacuum; irradiation of the films by incoherent beams and laser beams of different power and wavelength; spectral and diffractional methods of determination of film structure; chemical treatment of surfaces for structure fixation; development and verification of a model of photoinduced processes in films and on surfaces. We have developed methods of laser implantation of silver particles into thin waveguide films of argentic chloride and into melted quartz. It appears that colloidal solution of minute Ag granules is formed as a result of Ag implantation in AgCl at a low-power laser beam action. It is found that chains of Ag granules are created in AgCl-Ag films at monochromatic linearly polarized beam action. The chain orientation depends on orientation of the electric vector of inducing beam. Regular gratings are formed in light-sensitive films in two-beam geometry. We developed the method of one-dimensional or two-dimensional grating formation using a Wollaston prism as a beam splitter. This method is proposed for self-diffraction observation. To implant Ag into melted quartz a CO2-laser radiation ( ) was used. It was found that colloidal solution of Ag in quartz consists of Ag granules with diameter of about 6 nm. The solution is formed in the surface layer of quartz with thickness of about 50 nm. At that the colloidal absorption band is a Lorenz band (pointing out absence of particle dispersion in size), and it is situated at Frolich frequency. Results of the research may be used to form quasiperiodical structures in thin films of AgCl-Ag and As2S3-Ag, to implant silver particles into quartz by laser for fixing the surface silver nanostructures. In an educational process the results may be used in demonstrations on nonlinear phenomena just as self-diffraction. Product Description popup.authors popup.nrat_date 2020-04-02 Close