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Ceramic samples based on the microcrystalline powders (Cu1–хAgx)7GeSe5I (x = 0, 0.25, 0.5, 0.75, 1) were prepared by pressing them at the pressure close to 400 MPa and subsequent annealing at 873 K for 36 hours. Using the microstructural analysis, the average size of microcrystallites of these samples was determined. Investigation of electrical conductivity of ceramics based on (Cu1 хAgx)7GeSe5I solid solutions was carried out using the method of impedance spectroscopy in the frequency range from 10 Hz to 3×105 Hz and within the temperature range 293...383 K. Analysis of the Nyquist plots allowed determining the contributions of ionic and electronic components to the total electrical conductivity. The temperature dependence of ionic and electronic conductivity in Arrhenius coordinates is linear, which indicates their thermoactivation character. The compositional behaviour of ionic and electronic conductivity, as well as their activation energies have been studied. Their nonlinear character can be explained by the complex process of recrystallization and Cu+ ↔ Ag+ cation substitution within the cationic sublattice.

Nanocomposites based on urethane-acrylate monomers stabilized at high concentration of silica nanoparticles were fabricated and investigated with the aim to produce efficient volume Bragg grating elements. Their sensitivity in the green spectral region and high modulation depth of the refractive index in the optically recorded elements are determined by the redistribution of combined monomers and silica nanoparticles, by the property of initiators of polymerization as well as by the parameters of recording process. The developed materials and methods can be used for creation of versatile photonic elements, for manipulation of optical wavefronts or beam propagation, for optical sensing.

The influence of gold nanoparticles (AuNPs) on the decomposition of two widely used types of photoinitiators (Bis (.eta.5-2,4-cylcopentadien-1-yl)-bis (2,6-difluoro-3-(1H-pyrrol-1-yl)-phenyl) titanium/Irg784/and 2,2-Dimethoxy-2-phenylacetophenone/In2/) was investigated in this work, both, in simple toluene solutions or solutions with AuNPs, as well as in SiO2 nanoparticles and AuNPs containing monomer acrylate nanocomposites during photopolymerization. These processes are important for efficient, one-step creation of photonic structures by holographic recording based on polymer nanocomposites containing AuNPs with plasmonic properties. Analysing such processes, activated by irradiation with wavelengths of 532 nm and 325 nm, their efficiency and parameters of grating recording, as well as examining the related multistep photopolymerization processes by IR and UV–vis spectroscopy the influence of AuNPs on the decomposition of the photoinitiators was shown and explained by the mechanism of complex formation. Thereby, it is concluded that by combining the type of initiator, polymer matrix components, and illumination conditions the decomposition of initiators can be manipulated, that in turn affect the resulting optical modulation characteristics and the efficiency of the photonic elements recording in a one-step process.

In this work, the performance of gold nanoislands was investigated for Localized Surface Plasmon Resonance (LSPR) and Surface Enhanced Raman Spectroscopy (SERS) applications. Nanoislands were generated by thermally annealing thin layers of gold (having thickness in the 6–12 nm range), which was previously deposited by vacuum thermal evaporation onto glass substrates. Gold nanoparticles (AuNP) were evaluated based on their plasmonic and SERS performance and morphological properties. Scanning Electron Microscopy (SEM) was used to measure the average particle size and average interparticle distance in order to correlate them with the obtained plasmonic/Raman capabilities. The technological parameters of nanoisland fabrication for optimal performances were also determined.

In dentistry, it is necessary to increase the bonding strength between various bioinert zirconia ceramics and the luting cement in order to extend the lifetime of the restoration. As a new method, an ion source was used to implant silicon ions close to the surface of the zirconium-dioxide on nanoscale to improve chemical bonding in between the bonding agent and the zirconium-dioxide. This paper summarizes the main results of a unique technique to functionalize biomaterial surfaces with silicon ions produced by Electron Cyclotron Resonance Ion Source (ECRIS).

Sodium halogenthiophosphates Na6PS5Br and Na6PS5Cl as well as halogen-free Na7PS6 were synthesized by a two-step technique from elemental substances and relevant sodium halides. The elemental composition of the samples obtained was determined by energy-dispersive X-ray spectroscopy. The crystalline structure of the synthesized Na6PS5Br and Na6PS5Cl compounds is confirmed by X-ray diffraction and Raman spectroscopy. The Raman spectra of Na6PS5Br and Na6PS5Cl reveal a noticeable similarity to those of chemically related copper, potassium, and lithium halogenthiophosphates as well as the synthesized Na7PS6 compound. The electrical conductivity of Na6PS5Br, Na6PS5Cl, and Na7PS6 is shown to be predominantly ionic.

The publisher's version of this article can be viewed at https://link.springer.com/article/10.1007/s10853-017-0998-5 A read-only accessible version of this article can be viewed with this SharedIt link at http://rdcu.be/tB19

Compositional and fabrication method dependences of laser-induced geometrical surface relief formation in Ge Se amorphous layers were investigated with the aim to determine the possible role of initial conditions in the mechanism and efficiency of optical recording. The results show that pulsed laser deposition has some advantages in composition preservation and surface relief formation in comparison with thermal evaporation for producing layers with high sensitivity and efficiency of surface relief grating formation, especially in layers with Ge 24 Se 76 composition. It was shown that modulation depth of the created surface structures increases with increasing Se content in Ge Se amorphous chalcogenide layers. Thermal annealing has essential influence on the recording parameters, enabling additional insight into the possible mechanisms of light induced surface patterning in this type of light-sensitive amorphous chalcogenides. Raman spectroscopy was used to identify local structure of produced surface patterns.

Two-dimensional photonic crystal structures (PCS) were fabricated using a one-step recording process, multi-beam interference in smart polymer nanocomposites incorporating SiO2 and Au nanoparticles sensitized to 532 nm laser radiation. It was shown, that PCS with different geometry can be recorded in thick nanocomposite layers. The typical two dimensional (2D) PCS have square structure with 2–8 μm period, being in good agreement with theoretical structures obtained by mathematical modeling of the recorded PCS. The peculiarities of the photo-polymerization of nanocomposites with plasmonic Au nanoparticles were analyzed on the basis of Surface Plasmon Resonance Imaging (SPRi) and Raman spectroscopy investigations and used for the interpretation of the recording process and periodic structure formation.

The knowledge of viscosity, which determines the flow of material under applied stresses, is important for many processes of the material production. Data on viscosity of thin amorphous films are necessary for development of molding technology, which allows fast fabrication of various components for integrated optics. Chalcogenide films attract great attention due to their non-linear optical properties and possibility of viscosity variation by light illumination. Despite of importance of data on the film viscosity, no methods of their direct measurements were reported. We propose such method and apply it for measurements of viscosity of As20Se80 chalcogenide films in a temperature range 378–403 K. We have obtained that coefficients of viscosity vary in the range 3 × 107–1010 Pa·s, with the activation energy 2.9 eV. The thin film viscosity coefficients are 2–5 times smaller compared to those for massive glasses.

Following the modern and extremely useful direction of research and development of polymer nanocomposites with combined effects of photopolymerization superimposed by plasmon-induced processes, we investigated acrylate-based nanocomposites with broadband sensitive Irgaqure784 initiator and silicon oxide as well as gold nanoparticles in different regimes of illumination. The details of initiator photodecomposition and polymer chain formation mechanisms at the presence of the gold nanoparticles' (GNPs) plasmon fields and different combinations of irradiation wavelengths or intensities are discussed. These are related to the mechanism and efficiency of holographic volume and surface grating recording based on photopolymerization and mass-transport, diffusion processes of the organic matrix, and nanoparticles. GNP's presence in a monomer nanocomposite influences the recording parameters in a combined way, making preferable the double-wavelength irradiation mode, which may increase the efficiency of the recorded gratings up to two times at decreased exposures. Results may be used for planning fabrication processes of more complex, multifunctional photonic elements.

In this paper, the plasmon field enhanced light-induced changes are investigated in the amorphous Ge24Se76 layer incorporating Au nanoparticles. The presence of gold nanoobjects in amorphous chalcogenide/gold heterostructure influences the optical and structural properties, as well as volume changes of the material. It also enhances the Raman signal of the structure through surface enhancement, which allows clearer and better investigation of the glass structure and understanding of the mechanisms of surface plasmon stimulated transformations. In addition, it also enhances the recording of the optical grating pattern into the layer.

(Ag 3 AsS 3 ) 0.9 (As 2 S 3 ) 0.1 thin films with high concentration of silver were deposited by a rapid thermal evaporation, their structural properties were studied using SEM and AFM. Roughness analysis of as-deposited films surfaces was performed. The influence of laser and e-beam irradiation on structural and optical properties was analysed. It is shown that e-beam, as well as laser illumination, causes a formation of flakes, bubbles on the surface of the films. Holographic gratings were recorded on the given films using green laser. Optical transmission kinetics with laser illumination shows its increase with illumination time.

This paper is devoted to present the results of creation of gold nanoparticles on titanium surface. We focused on the problem how to create gold nanoparticles on the titanium surface with defined particle size and distribution, which could be interesting for several applications (e.g. providing well-defined substrates for biomedical research, etc.). To do that the sample is affected by the complex physical rout of gold nanoparticles formation: by gold ion implantation, thin Au layer deposition and thermal annealing. The effect of the technology, influence on the surface structure and its parameters were investigated by the X-ray diffraction, Scanning Electron and Atomic Force Microscopy, as well as by Secondary Neutral Mass Spectrometry methods.

Rare-earth-doped optical materials are important for light sources in optoelectronics, as well as for efficient optical amplification elements and other elements of photonics. On the basis of the previously developed method of anhydrous, low-temperature synthesis of Er/Yb oxides from their chlorides we fabricated proper nanoparticles with defined parameters and used them for the development of optically transparent, luminescent polymer nanocomposite with low optical scattering, suitable for direct, light-induced formation of photonic elements. Introduction of preformed gold nanoparticles in such a nanocomposite was also performed and an enhancement of luminescence due to the influence of plasmon effects was detected.

(Ag3AsS3)0.6(As2S3)0.4 thin films were deposited using rapid thermal evaporation (RTE) and pulse laser deposition (PLD) techniques. Ag-enriched micrometre-sized cones (RTE) and bubbles (PLD) were observed on the thin film surface. Optical transmission spectra of the thin films were studied in the temperature range 77–300 K. The Urbach behaviour of the optical absorption edge in the thin films due to strong electron–phonon interaction was observed, the main parameters of the Urbach absorption edge were determined. Temperature dependences of the energy position of the exponential absorption edge and the Urbach energy are well described in the Einstein model. Dispersion and temperature dependences of refractive indices were analysed; a non-linear increase of the refractive indices with temperature was revealed. Disordering processes in the thin films were studied and compared with bulk composites, the differences between the thin films prepared by RTE and PLD were analysed.

We have detected that surface relief gratings (SRG) in amorphous chalcogenide films As20Se80 can be optically recorded at low temperature, such as 77 K. A diffusion mechanism of photo-induced (PI) mass transport is proposed. A driving force of PI mass transport is a lateral steady state electric field induced by light interference. The kinetics of PI SRG growth depends on temperature due to temperature dependence of PI diffusion coefficients and concentration of radiation defects. By comparison of low temperature kinetics with that at 300 K we estimated diffusion activation energy, which turned out 0.09 eV. We present a model that explains low diffusion activation energy.

Direct surface relief recording in amorphous chalcogenide semiconductors like As20Se80 and other compositions from As(Ge)–S(Se) systems essentially depends on the chemical composition, technology, and the recording conditions, resulting discrepancies in the results and interpretations. We have developed a method of direct comparison of the relief height and form in a combined thin film samples made of the reference and investigated compositions, as well as simple way of determining the efficiency of mass transport at surface relief recording. Selection of the a-Se as reference layer enables consideration of the possible role of composition, temperature, polarization in the recording process for any other chalcogenide or other material, which possess similar relief recording effects.

Nonlinear refractive indices of simple and composite chalcogenide glasses with gold nanoparticles are measured by the Z-scan method using a femtosecond Ti:sapphire laser with a central wavelength of 800 nm and a pulse duration of 40 fs. It is shown that introduction of nanoparticles into thin layers of amorphous GeS2, As30Ge20S50, and As3Ge35S62 leads to a decrease in the total nonlinear refractive index due to additional absorption of femtosecond laser radiation without efficient excitation of localized plasmons outside the resonance region. For example, the nonlinear refractive index decreases with addition of gold nanoparticles from 16.1 × 10–12 to 13.0 × 10–12 cm2/W for GeS2, from 3.9 × 10–12 to 3.2 × 10–12 cm2/W for As30Ge20S50, and from 5.8 × 10–12 to 4.7 × 10–12 cm2/W for As3Ge35S62.

Surface reliefs in the form of dots and surrounding rings were recorded by focused laser beam on bulk amorphous selenium samples with an aim to separate the possible contributions of pure light- and thermally stimulated effects to the relief formation process. It is concluded, that heating by the light beam can be cross-linked with light induced mass transport in the gradient of illumination and temperature fields and so with surface relief formation, influencing its efficiency and quality. Such thermal effects should be taken into account in light sensitive chalcogenide glasses with low softening temperatures and possible crystallization effects.

Our investigations relate to the development of new polymer nanocomposite materials and technologies for fabrication of photonic elements like gratings, integrated elements, photonic crystals. The goal of the present work was the development and application of the multi-beam interference method for one step, direct formation of 1-, 2- or even 3D photonic structures in functional acrylate nanocomposites, which contain SiO2 and Au nanoparticles and which are sensitized to blue and green laser illumination. The presence of gold nanoparticles and possibility to excite plasmonic effects can essentially influence the polymerization processes and the spatial redistribution of nanoparticles in the nanocomposite during the recording. This way surface and volume phase reliefs can be recorded. It is essential, that no additional treatments of the material after the recording are necessary and the elements possess high transparency, are stable after some relaxation time. New functionalities can be provided to the recorded structures if luminescent materials are added to such materials.

The focus of this work is on the formation of a lithography-free redox conductive bridge memristor array, comprised of different compositions of GexSe1−x chalcogenide glasses with the aim of selecting the chalcogenide material that provides the best performance. Various memristive arrays were fabricated on a metal–chalcogenide–metal stack. This structure offers high device density with the simplest configuration and allows access to each nano redox conductive bridge device. It was found that the device stability and threshold voltage were a function of the chalcogenide glass composition, with the Ge-rich film contributing to the best device performance, which is attributed to the formation of rigid structure and the availability of Ge–Ge bonds. Additionally, these parameters were dependent on the thickness and the surface roughness of the chalcogenide glass. Application of a nonlithography method for fabricating the array structure offered excellent yield, stable ON–OFF states and good uniformity. This demonstration, along with success achieved at the single cell level, suggests that the redox conductive bridge memristor is well positioned for ultrahigh performance memory and logic applications.

In Au/As2S3 metal-semiconductor surface composite structures, anomalous absorption of light beyond the fundamental absorption edge of the semiconductor is observed. This absorption is caused by the interaction of the near field of surface plasmons in metal nanoparticles with interference (virtual) modes of the Fabry-Perot cavity formed by the semiconductor film.

Two types of amorphous functional materials, based on light-sensitive inorganic compounds like Se and As20Se80 chalcogenide glass (ChG) were investigated with the aim to establish the influence of plasmonic fields, excited by the recording light in nanocomposite layers made of these compounds and gold nanoparticles on their photomechanical response. Both these basic materials are characterized by pronounced photoplastic effect and used for real-time optical recording of optoelectronic elements (based mainly on surface relief gratings) due to high photofluidity and polarization-dependent mass-transport. We have established that mass-transport processes in these ChG can be enhanced in the presence of localized plasmonic fields generated by light if the condition of surface plasmon resonance (SPR) is fulfilled. The subjects of special interest are the mass-transport processes at nano-scale stimulated in the nano-composite layers either by uniform or periodically distributed optical fields. It was found that irradiation by light in the presence of SPR really enhanced the efficiency of mass-transport and produced surface nanostructurizations. The variation in the topography follows closely and permanently the underlying near field intensity pattern. Nanostructurization of photosensitive amorphous As20Se80 film by surface plasmon near field irradiation.

International audience; Amorphous selenium (a-Se) is the simplest model material for investigation of the well-known photoinduced structural and optical transformations in amorphous chalcogenides. Since a lot of parameters and characteristics of materials essentially change at nanoscale, we applied nanostructuring to a -Se in nanomultilayers, obtained by pulsed laser deposition. The enhancement of photo- and thermally-induced crystallization was observed in a-Se/aluminosilicate nanomultilayers due to the initially heterogeneous state of Se in such samples, in comparison with single a -Se layers.

The influence of the localized surface plasmon fields on the light stimulated transformations in amorphous chalcogenide films was investigated. It was established that both in the gold nanoparticle array-chalcogenide film and in the gold film with nanohole array-chalcogenide film composites the plasmon fields, induced during the laser illumination of the structures, increase the efficiency of structural transformations, the related photo-darkening or bleaching, as well as of the volume change, surface deformations. The results, obtained for structures with As 20 Se 80 amorphous layer, can be applied for other selected chalcogenide layers and fabrication of locally driven information recording media.

Homogeneous TiO2–acrylate nanocomposite with low optical scattering were prepared by UV curing. The surface of the nanoparticles was modified by carbonic acids to control the aggregation between the nanoparticles. Effects of TiO2 content on the properties of nanocomposite (transmission, refractive index, mechanical properties, internal structure) were investigated. Depending on the composition of the matrix hard materials with high refractive index or light sensitive layers for holographic recording can be obtained. The first are interesting for medical applications, the last for photonics. For example, TiO2 nanocomposite was used for in situ fabrication of holographic gratings by interference lithography. Formation of the grating samples with high diffraction efficiency (20 %) is based on the light-stimulated mass-transport processes in the polymerized layer during the recording without any additional treatments. The relief formation has been investigated by AFM measurements too. These materials are designed for applications in integrated optics, elements of optics, in nanolithography.

Patterning processes in amorphous Se and $$\hbox {As}_{20}\hbox {Se}_{80}$$ films at short electron beam pulses (from 200 ns to 100 ms) were studied for the first time. The surface reliefs occurring as after-pulses effects were recorded and analysed. Giant hillock formation was detected at about $$200\,\upmu \hbox {s}$$ pulses while very small changes in surface morphology were observed at other pulse durations. The obtained data indicate that the strong increase in e-beam sensitivity of mechanical response (giant surface hillock formation) at about $$200\,\upmu \hbox {s}$$ is due to some resonance effect. A qualitative description is given, relating these times to the characteristic generation and relaxation time of the defects in these materials, which illuminates the process of e-beam induced structural rearrangement. The measurement has been performed at room temperature and at $$-120\,^{\circ }\hbox {C}$$ and only a 20% change in the maximal pattern height has been detected.

Cu 6 PS 5 I thin films were deposited onto silicate glass substrates by non-reactive radio frequency magnetron sputtering. Spectrometric and isoabsorption studies of Cu 6 PS 5 I thin films in the temperature interval 77–500 K were performed. Structural studies were carried out using X-ray diffraction and scanning electron microscopy techniques. Temperature evolution of optical transmission spectra as well as temperature dependences of optical pseudogap and Urbach energy is investigated. The influence of temperature-related and structural disordering on the Urbach tail is studied.

Here we demonstrate a plasmon enhanced optical recording in As-Se layers, which are among the most applicable for processing with He-Ne or other red light emitting lasers. Gold nanoparticles deposited on the silica glass substrate and covered by an amorphous chalcogenide layer satisfy the conditions of efficient surface plasmon resonance in this spectral region. The enhancement of photo-induced transformations results in an increased rates of photo-darkening, followed by bleaching and localized volume changes. These experimental results support the importance of localized electric fields in photo-structural transformations of chalcogenide glasses as well as suggest new approaches for improving the performance of these recording media. (© 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The photo-stimulated interdiffusion within chalcogenide based nano-layered structures (NLS) produces large changes in properties, which have potential application in optical pattern recording. The mechanism of these changes is investigated for two NLS consisting of 100 alternate layers of antimony and As 2 S 3 , but of different relative thicknesses, by high-resolution X-ray photoelectron spectroscopy. The results suggest the formation of Sb–S bonds at the expense of As–S bonds, with a consequent increase in the refractive index but minimal change in thickness. The role of oxygen in photoinduced transformations, especially in the top layers, is characterized and discussed.

The preparation technology of chalcogenide glass-superionic conductor nanocomposites was developed as a Cu_6PS_5I nanocrystalline superionic conductor, incorporated in glassy matrix As_2S_3. The structural studies by the method of scanning electronic microscopy are performed as well as electrical conductivity of the nanocomposite are investigated. The temperature dependence of the optical absorption edge of nanocomposite is studied ; the non-Urbach behaviour of the absorption edge is revealed. The influence of different types of disordering on optical absorption edge is studied.

The light and heat induced changes in the optical band gap of Sb/As 2 S 3 nanomultilayered chalcogenide film has been studied. Even though the changes in optical bandgap are attributed to the light and heat induced interdiffusion, the diffusional intermixing between the layers is rather different with light and heat. The observed difference in the light and heat induced interdiffusion is due to unequal diffusion coefficients of light and heat predicted by thermal spike model.

We report the in situ optical transmission change in the complete visible region of the electromagnetic spectrum to asses the kinetics of photo induced interdiffusion in Sb/As2S3 nanomultilayered film. The interdiffusion of Sb into As2S3 matrix results in the formation of Sb-As2S3 ternary solid solutions which is explained by the change in optical band gap, absorption coefficients and Tauc parameter (B-1/2) with evolution of time. The wavelength dependence of the time constants provides a better description of photo induced effects. The time evolution of the absorption coefficients and optical band gap are significantly faster in this process. (C) 2009 Elsevier B.V. All rights reserved.

Investigations of light-induced volume expansion and surface pattern recording in amorphous chalcogenide layers and nano-layered structures (NLS) were extended to direct electron-beam recording on Se/As 2 S 3 and Sb/As 2 S 3 NLS. Light as well as e-beam induced bleaching occurs in all NLS, while volume expansion occurs only in chalcogenide–chalcogenide NLS and in homogeneous Se or As 2 S 3 layers. Comparison of these two phenomena revealed the possible role of purely electronic and thermal processes in the interdiffusion and relief formation. The latter is supposed to be connected with radiation-induced defect creation, free volume increase under the increased fluidity conditions as well as with the possible additional influence of electrostatic forces and stress.

In this work the performance of Au/Ag nanoislands was investigated for Surface Enhanced Raman Spectroscopy (SERS) and Localized Surface Plasmon Resonance (LSPR) applications. The nanoislands were generated by thermally annealing thin layers of silver and gold (having thickness in the 5-15 nm range), which were previously sputtered onto glass surfaces. Both pure (silver and gold nanoparticles – AuNP and AgNP) and composite metallic systems (silver-gold core-shell structures – Ag-Au core-shell) were evaluated based on their plasmonic and SERS sensitivity. Atomic Force Microscopy (AFM) and Scanning Electron Microscopy (SEM) were used to measure the size, shape and distribution of the nanoparticles to correlate them with the obtained plasmonic/Raman capabilities. The technological parameters of nanoisland fabrication for optimal sensitivities are presented.

Metal nanoparticle-semiconductor interfaces are sites of complex light-matter interactions, in particular, the exciton-plasmon coupling which plays a key role in the optical response of such heterostructures. There exists a pathway of photoinduced charge transfer from the semiconductor to the metal, which can be used to controllably vary the driving forces at the interface that leads to tunable optoelectronic properties. In this letter, we report the observation of a dramatic suppression of plasmonic as well as excitonic absorption in a-Ge24Se76/gold nanoparticle heterostructures by trapped charges. Suppression of the excitonic absorption is strongly correlated with the plasmon wavelength. (C) 2016 Author(s).

The high spatial resolution of the localized structural transformations induced by different irradiations in amorphous chalcogenides, as well as the possibility of inducing volume expansion, promotes applications of these inorganic resists for optical recording, data storage and makes them attractive for nanolithography. This paper focuses on the fabrication of surface reliefs at submicrometer length scales in a direct, one-step process of recording by light or ion beam on Se layers or Se/As2S3 nanolayered films due to induced volume expansion.

The effects of light- and thermally stimulated interdiffusion in Se/As2S3 nanomultilayers (NML) with modulation period of 6–9 nm fabricated by pulsed laser deposition (PLD) and by the method of cyclic thermal evaporation (CTE) of the Se and As2S3 components were investigated by means of direct low-angle X-ray diffraction (LAXRD) measurements and by indirect methods of optical measurements. More pronounced nano-granular structure is characteristic for PLD samples but at the same time the interfaces are essentially sharpened, the periodicity and the initial blue-shift of the optical absorption edge are better in comparison with CTE samples. Somewhat less efficient interdiffusion and changes of optical parameters i.e. amplitude-phase recording in PLD samples in comparison with CTE ones may be caused by different deposition conditions, ratio of sub-layer's thickness and their structure, eventually by changes in chemical composition.

Thin As2Se3 amorphous chalcogenide films have been studied by nanoindentation and atomic force microscopy in darkness and under illumination by band-gap light. The combination of these two methods has been used to study the peculiarities of the photoplastic effect in amorphous semiconductors. It has been shown by multiple loading indentation experiments that a non-linear mechanism of the formation of the strain response is realized in the As2Se3 films subjected to the combined action of light and external mechanical loading. We have observed that light illumination alters the internal friction of the films and their shear modulus. These observations have been considered in the frame of the two-phase model of chalcogenide glasses. Some arguments in favor that the self-organization processes take place in the structure of irradiated film are given.

Bi 2 S 3 –As 2 S 3 composite formation was performed by two methods: by the direct insertion of Bi 2 S 3 nanocrystals into a molten As 2 S 3 glass which was further solidified and by the crystallization of a rapidly quenched (As 2 S 3 ) 1− x (Bi 2 S 3 ) x glasses with x = 0.005, 0.01, 0.02 and 0.04 at different conditions. Fine tuning of the annealing of the quenched glass as well as the mixing of nanocrystals in to the molten glass resulted glass-crystalline composites with different amounts and distribution of 20–50 nm large Bi 2 S 3 nanocrystals as well as larger, up to few micrometer long, needle-like crystals. Structural and optical investigations support the presence of the Bi 2 S 3 crystalline phase in all composites. Optical absorption and the photoconductivity of bulk composite samples follow the structural changes of the structure in the amorphous and amorphous-crystalline phase. In addition, the 290 cm −1 characteristic band in Raman spectra may be used for tracing the formation of the nanocomposites.