Abstract. We have established that mass-transport processes in two types of amorphous materials, based on light-sensitive inorganic compounds like Se and As 20 Se 80 chalcogenide glasses (ChG), can be enhanced at the nanoscale in the presence of localized plasmonic fields generated by visible light in gold nanoparticles (GNPs), if the condition of surface plasmon resonance (SPR) is fulfilled. It was found that irradiation by light in the presence of SPR produces profound surface nanostructurizations, and variation in topography follows closely and permanently the underlying near field intensity pattern. We have proposed a model of mass-transport in which the existence of moving anisotropic dipolar units and internal electric field in ChG as a main driving force of this movement is suggested.

By the method of rapid radiation heating (at a speed of 20-25 K/s) of Au and Ag films with a thickness of 4-35 nm to temperatures of 573-693 K in air and in the process of vacuum deposition of silver on heated (up to 700 K at a heating rate of 10 K/s ) glass substrates formed Au and Ag NPs arrays with nanoparticle sizes from several tens to hundreds of nanometers, the position λSPR of which is in the range of 520-597 nm for Au NPs and 424-509 nm for Ag NPs. It is established that the average size of nanoparticles depends on the thickness of gold and silver films and the annealing temperature. The results testify that glass substrates with arrays of randomly distributed gold NPs can be used as effective SERS-substrates for the investigation of Raman spectra of nanosized (50-100 nm) chalcogenide films.

Using the planar structures "Ni layer - chalcogenide amorphous film - Ni layer" and "graphite probe - chalcogenide amorphous film graphite probe" samples, the influence of mercury vapor on the electrical resistance of amorphous films of the Se-Te, Se-Sb and Se-As systems was investigated. It was established that exposure of samples in mercury vapor leads to a decrease in their electrical resistance by 4-7 orders of magnitude. As the temperature and mercury concentration increase, the transition time from a high-resistance state to a low-resistance state decreases. When introducing Te, Sb, and As into amorphous selenium and increasing their concentration in the composition of the films, the transition time increases, and the value of the change in resistance decreases. It was established that the change in resistance is mainly determined by the change in surface conductivity of chalcogenide films. A decrease in the electrical resistance of selenium-containing amorphous films modified with mercury is caused by the formation of HgSe crystalline inclusions in their matrix.

The effect of plasmonic nanostructures (NSs) on the Raman spectra and underlying structural changes in thin chalcogenide films is investigated. Several tens of nanometers thick As 2 S 3 and Se films were deposited by thermal sputtering on glass and surface-enhanced Raman spectroscopy (SERS) substrates based on gold nanostructures for comparison. The films on glass were practically not detectable by the Raman spectroscopy. Using gold NSs as the substrates enabled reliable registration of the Raman spectra of both the As 2 S 3 and Se films. The registered Raman spectra contained all the features usually present in the films with the thicknesses ~1 μm or more. Based on our analysis of the spectra obtained at different excitation wavelengths, we may conclude that the SERS chemical mechanism makes the main contribution to the enhancement of the Raman signal from chalcogenide films. Adjustment of the parameters of SERS substrates to tune their plasmon band position in resonance with the excitation laser radiation enables increasing the plasmonic enhancement contribution. Besides the effect of enhancement, localized plasmon resonance in the gold NSs causes local heating of the chalcogenide film around them leading to local structural transformations, which can be controlled using the Raman spectra.

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