The effect of photoinduced anisotropy and its application to vector hologram recording is reviewed focusing on amorphous chalcogenides. Vector holographic grating recording in amorphous As-S-Se(a-As-S-Se) films is experimentally studied and analyzed in comparison with scalar recording. It is holographically established that a linearly polarized 632.8 nm light produces photoinduced anisotropy and the chalcogen related D⁺, D^- center reorientation and generation mechanism is proposed. It is used to explain the observed peculiarities of vector recording in comparison with scalar recording based on photoinduced structural changes: much lower diffraction efficiency (4 X 10^-3% versus 4%), much larger specific recording energy [6.4 kJ/(cm²%) versus 20 J/(cm²%)], difference in spatial frequency response, instability (vector hologram lifetime of about two days versus practically permanent scalar holograms), the absence of hologram self-enhancement (present in scalar recording), near perfect reversibility. It is also experimentally found that vector holograms in a-As-S-Se films indeed reconstruct the signal wave polarization but only in the minus first diffraction order. It is also shown that photoinduced anisotropy also contributes to the scalar hologram recording in amorphous chalcogenides stimulating it by means of subbandgap readout light and enabling a subbandgap recording.

The estimation of information quality -- value which takes into consideration both system information capacity and rate of data arbitrary access -- has been performed for the volume holographic memories. It has been shown that if the technical possibilities are limited, the super high information capacity of the volume holographic memories exceeds those of the other kinds of memory.

The polarization self-modulation effect has been applied for the effective measurement of the characteristic response time of nominally pure Bi₁₂SiO₂₀ at wavelengths of 810 nm and 980 nm. Owing to the oxygen deficiency in the crystal lattice, the studied BSO crystals have shown the unusual photorefractive sensitivity and the remarkable operation speed in near infrared spectral region. The response time of 130 ms has been measured at the wavelength of 810 nm and the response time of 540 ms at 8 equals 980 nm with the incident intensities of 110 mW/cm² and 200 mW/cm², respectively. To our knowledge this is the first experimental evidence of subsecond response in the infrared for the non- semiconductor photorefractive material.

A review of the generation of photoconductive line patterns in semiconductors and their possible use in free-space electromagnetics is presented. The basic configurations and properties of conductive line antennas and frequency-selective and chiral surface are listed. Tracking antennas based on photoconductive gratings on silicon are considered in detail. Some experimental results of investigation on the photoconductivity of A_IIB_VI monograin powder films at high frequencies are reported. The persistent photoconductivity in doped semiconductors containing DX and AX centers is reviewed.

Information input, storage, and sampling using the holographic methods can be performed as a result of using some processes part of which are thermal, and some of the others depend on the temperature modes. Depending on the way how do these processes go, the most important characteristics of the holographic systems (such as the stored information density and amount, information transmission rate, and information quality) can vary. The behavior of the listed characteristics on the temperature modes of information recording, storage, and sampling has been considered in the presented paper qualitatively.

An automated pulsed holography camera system for ultra-large format display holography has been created. This camera produces reflection and rainbow copies of up to 110 X 150 cm size as well as master holograms of up to 80 X 100 cm size. In addition, the system is capable of generating digital full color transmission rainbow holograms from masters produced by a digital mastering machine. Camera utilizes the single longitudinal mode-phase conjugated laser delivering the pulses of 35 ns duration with maximum energy of 8 J at 526.5 nm wavelength. High output energy have conditioned the use of non-spherical spatial beam filtering in each beam pass. Camera incorporates instant switch-over from copying to mastering modes, permits digital electronic setting of all beam ratios and allows manual tuning of scene illuminating diffusers. Some of the most important applications of this camera are printing of AO format 3D-drawings for advanced virtual prototyping of machines & devices, large format scientific & artistic holography, 3D-posters printing industry of near future.

The indentation creep in as-deposited and photopolymerized As- S-Se and As-S films has been investigated. The results show pronounced relaxation of mechanical stresses in the films at room temperature. The relationship (sigma) equals B (epsilon) ^m between the deformation rate and the stress is observed and the values of the deformation rate sensitivity exponent m < 1 are found. The creep rate was found to be dependent on deposition conditions of layers, applied indentation load, structural state of the material and light irradiation during the creep test.

This work deals with electrophotographic parameters and structure of Se layers evaporated in vacuum upon aluminum or glass substrate. Prior to evaporation, a conducting polymer film covered the substrate -- this improves layer adhesion to the substrate. A phosphorous or tellurium sublayer was evaporated upon a thus prepared substrate. The tellurium sublayer speeds up crystallization of selenium (even at temperatures equal to room temperature, crystalline selenium sublayer forms between the amorphous selenium layer and tellurium sublayer). For this reason, layer sensitivity in the long-wavelength spectral region increases, whereas decrease of potential of a positively charged layer slows down, and the achievable potential increases. Evaporation of the amorphous selenium layer upon a phosphorus sublayer does not cause a significant change of electrophotographic properties of the layer, but formation of selenium crystals on the substrate ceases. Phosphorus neutralizes crystallization centers, which are present on the substrate (for example, tellurium islands, upon which phosphorus is evaporated, does not stimulate formation of selenium crystals any more. The same effect is observed if tellurium islands are evaporated, does not stimulate formation of selenium crystals any more. The same effect is observed if tellurium islands are evaporated upon phosphorus sublayer). Results presented in this work can be used in manufacture of an amorphous selenium layer without a crystalline selenium sublayer, or with a crystalline sublayer with a desired thickness.

The photo- and electron beam induced changes in solubility of amorphous chalcogenide semiconductor As-S-Se and As₂S₃ thin films have been studied. The possibilities of practical application of these materials as resists for the production of relief holograms and holographic optical elements are discussed. It is shown that the self-enhancement phenomenon of holographic recording in amorphous chalcogenide semiconductor films by light or thermal treatment can be used to increase the diffraction efficiency of the holograms.

CdS, ZnS and CuS thin films were prepared by spray pyrolysis method using metal chlorides and thiourea (tu) as starting materials. Metal sulfide films form as products of thermal decomposition of complexes Cd(tu)₂Cl₂, Zn(tu)₂Cl₂ and Cu(tu)Cl(DOT)1/2H₂O, originally formed in aqueous solution at precursors molar ratio 1:2. The metal-ligand bonding is thermally stable up to 220 degrees Celsius, followed by multistep degradation process of complexes. The TG/DTA analysis show similar thermal behavior of complexes up to 300 degrees Celsius with the formation of metal sulfides in this decomposition step. In air intensive oxidation processes are detected close to 400, 600 and 720 degrees Celsius for Cu, Cd and Zn complexes, respectively. The results of thermoanalytical study and XRD of sprayed films show that CdS and ZnS films could be grown at 450 degrees Celsius even in air while deposition of copper sulfide films should be performed in an inert atmosphere. High total impurities content of 10 wt% in CdS films prepared at 240 degrees Celsius is originated from the precursor and reduced to 2 wt% by increasing the growth temperature up to 400 degrees Celsius.

We review critically recent results of investigation of hydrogenated amorphous silicon (a-Si:H) and Si⁺- implanted SiO₂ films from the point of view of light- emission applications. Wide bandgap a-Si:H with the energy gap ranging from 2.0 to 2.2 eV exhibits room temperature photoluminescence in the visible region. Electroluminescence, however, occurs after previous recrystallization of a-Si:H only and seems not to be perspective for large scale applications. Si⁺-implanted SiO₂ films contain, after proper annealing at 1000 - 1100 degrees Celsius, Si nanocrystals that luminesce in the red. In parallel another emission band can occur (in the blue region) which is related to post-implantation defects. We demonstrate that in SiO₂ films homogeneously implanted across the entire film thickness red electroluminescence can be easily observed, presumably due to injection of electron-hole pairs into Si nanocrystals. Finally, the present status of prospects of stimulated emission achievement in low-dimensional Si structures is briefly summarized.

We describe a novel phenomenological model for transmission through an adiabatic 1-dimensional constriction, where the electronic configuration around the middle of a quantum point contact can be in two configurations: the usual ground state with spin neutrality (S equals 0) and a higher (virtual) isomer with an uncompensated electronic spin (S equals 1/2), which modifies the conductance at higher temperatures, where it is thermally populated, giving rise to the so-called 0.7 structure. Bias spectroscopy reveals the energy difference between the two isomers. The isomer reflects the charge/spin separation in the middle of the constriction. The high energy isomer is a spin 1/2 state (but not magnetically ordered), and will not directly contribute to the transmission unless temperature is high or biasing allow a Kondo-like resonant transmission. The resonant transmission represents a reduction in conduction from the fully quantized value, 2e²/h.

Properties of strongly localized excitons in heterostructures of CdTe/CdMnTe are described. Strong localization effects, which modify properties of excitons, are related to micro- structure characteristics of the sample studied. We demonstrate that at low temperatures excitons in the structure with 68% Mn fraction in the CdMnTe barriers are quasi-zero- dimensional.

New results of the numerical and experimental investigation of compact solid-state lasers with pulse compression by backward stimulated scattering and multipass laser amplifiers are presented. New models of the master oscillator with the combined passively and actively Q-switched Nd:YAG produce single-mode pulses whose energies are approximately 6 mJ, duration < 2 ns and timing jitter approximately 5 ns. Investigations of Cr⁴⁺:YAG crystal bleaching by 150 ps and 2.3 ns long pulses with the Gaussian intensity distribution permitted to obtain more reliable values for ground and excited state absorption cross sections. Application of the active Q-switching with negative feedback enabled to achieve synchronized single-mode pulses with the duration of < 2 ns and the energy of approximately 7 mJ with energy deviations of +/- 1.5% and timing jitter of < 0.5 ns. It is shown that the SBS-compressor filled with heavy fluorocarbons and pumped by amplified (approximately 40 mJ) symmetrical short (approximately 2 ns) pulses can produce the Stokes pulses with 25 mJ energy and the duration as short as 90 ps. A modified Nd:YAG laser with a hybridly Q-switched master oscillator and heavy freon as a Brillouin medium and a multipass Nd:YAG amplifier can generate pulses with the duration of approximately 100 ps and the energy of > 0.6 J at repetition rates of approximately 10 Hz with pulse jitter approximately 1 ns.

Porous GaAs layers obtained by electrochemical etching were investigated using SEM, AFM and optical methods. It was established that increasing etching duration and current density change the porosity of bulk GaAs and at the same time, both gallium and arsenic oxides are formed on the sample surface. Photoluminescence spectra of investigated porous layers consist of 'infrared' and 'green' spectral structures. The 'infrared' structure exhibits a red-shift of its peak energies, and intensity of 'green' structure is highly dependent on etching conditions. Possible reasons of origin and of changes in those spectra are discussed.

Lateral electric field (up to 2 kV/cm) effects on light transmittance near the fundamental edge absorption in selectively doped p-type In_0.21Ga_0.79As/GaAs heterostructure with Zn delta-doped barriers have been investigated. The hole distribution function modulations were calculated using the light transmittance modulation data. Fluctuations of the quantum well parameters were taken into account.

LaF 3 is presented as a possible high refraction index material for the interference coatings down to wavelength of 145 nm, if well-purified. A material shows up a negative inhomogeneity. The optical parameters of evaporated LaF3 layers are presented. The best mirrors based on LaF3-MgF2 system have a reflectivity up to 99% depending on absorption in layers.

A detail study of both the optical and electrical low- frequency noise spectra and their correlation factor of graded-index separate-confinement-heterostructure, multiple quantum well strained-layer Fabri-Perot and distributed- feedback InGaAsP/InP laser diodes has been carried out under the wide current and temperature ranges. A particular attention was concentrated to the investigation of optical and electrical fluctuations due to the mode hopping effect, which was observed at specific forward currents and temperatures. Both electrical and optical noises at mode hopping areas have the Lorentzian type spectrum, and are very strongly correlated and very sensitive to temperature and facet reflectivity.

This work represents the results of synthesis and research of the thin film properties based on EuO-CeO₂ system, which alter their properties in dependence on percent concentration of one of components. It was obtained that double-composition EuO-CeO₂ oxide films with EuO content of 30 - 40 weight % demonstrate the extreme properties: a minimal dark conductivity is 10^-10 (Omega) ^-1m^-1, a maximal photo-sensibility and nonlinearity of current-voltage characteristics is 1.48, a minimal temperature resistance coefficient is 10^-3 1/degree. In particular, the rare- earth semiconductor photoconductivity kinetics is connected with decreasing of photoconductivity relaxation time at illumination intensity gain. At illumination intensity of I equals 10⁵ - 10⁶ W/cm² the photoconductivity relaxation time has been found to be 10^-10 sec.

New model explaining fast charge separation from the initially excited charge transfer (CT) states is presented in this paper. According to our suggestion a substantial dipole moment is localized in the CT complex after its optical excitation. Being a strong local perturbation this electronic dipole induces the changes in the equilibrium positions of atoms and molecules in the vicinity of its surrounding. Some particular modes are not overdamped at the very initial times while the rest of the modes evidently are responsible for the presence of the heat bath and thus for the energy dissipation. In the case when these specific modes are strongly coupled with the electronic subsystem, they can crate the driving force for the charge transfer via the feedback of the nonrelaxed environment. This model is demonstrated in the framework of the modified Marcus approach. Specific conditions for the oscillating behavior and relaxation rates in order to obtain the increase of the charge transfer is discussed.

The problem of charge carrier photogeneration in conjugated polymers is related to the question concerning the singlet excitation binding energy. Measurements of the cw- photoconduction in several conjugated polymers as a function of photon energy, electric field, and temperature under different cell geometries indicate that excitons can dissociate at an electrode as well as via sensitization in the bulk. Intrinsic photogeneration can also occur at higher photon energies via dissociation of vibrationally excited singlet excitons. Charge transport, monitored via time-of- flight signals, can be rationalized in terms of a disorder concept except for a ladder-type poly-(para-phenylene) film in which built-in disorder is weak.

In this report the differences and identities of charge carrier drift by measuring drift of photo-excited carriers according to subnanosecond TOF integral mode are compared to drift of equilibrium carries investigated by CELIV method in thin (0.1 - 1.1 micrometer) layers of poly(p-phenylene vinylene) (PPV) polymer. From TOF measurements we obtained that the very initial mobility of photogenerated holes relaxes from the value of the order of 10^-2 cm²Vs down to the values of the order of 10^-5 cm²/Vs within nanosecond time duration.

The excitation dynamics in indandione-1,3 Pyridinium Betaine (IPB) intramolecular charge transfer molecules in various environments was studied. By comparing the excitation properties of the IPB molecules in solution and those in the crystal form, the influence of the intermolecular interactions on the excited state dynamics is considered. Two types of excited states are revealed in the IPB crystal: the Frenkel exciton states, which cause ultrafast nonradiative excitation decay, and the intermolecular charge transfer exciton states positioned below the Frenkel states, that have a longer lifetime and are responsible for pronounced photocurrent efficiency of IPB solids.

Our report is on the observation of thermoelectric phenomena in polymer dispersed nematic liquid crystal (PDLC). We have performed electro-optical measurements of the PDLC composite material based on both polyvinylbutiral and epoxy resin matrix. Despite different preparation al methods of the PDLC films, they show at the same time both the properties of polymer and liquid crystal. A stable memory effect was observed in the investigated PDLC films.

The present publication is devoted to the studies of the azo- hydrazone tautomerism of some 3,5-dialkyl substituted azobenzenes. Four new 3,5-dialkyl-4-hydroxy azobenzenes containing electron acceptor SO₂ groups were synthesized and investigated in solutions, vacuum evaporated (VE) films and doped polymer films. We have observed that azo-hydrazone tautomeric equilibrium depends on the structure of the molecule and the polarity of the solvent. VE films of compounds containing a primary sulfonamide group SOP₂NH₂ exhibit predominating azo form absorption band at about 365 nm, which decreases or disappears on UV irradiation giving rise to characteristic hydrazone absorption band at 430 nm. For the thin VE films of related derivatives containing a secondary sulfonamide group SO₂NHC₄H₉ we have observed predominating hydrazone form absorption band at about 430 nm or a broad band at 380 - 430 nm suggesting a tautomeric mixture. Reversible trans-cis isomerization of 3,5-dimethyl-4- hydroxy azobenzenes containing secondary sulfonamide group in the doped PMMA film was investigated.

Derivatives of trinitrofluorenone, bisphenylquinone, thiopyran, oxadiazole, anthraquinone may be mentioned as electron transporting materials (ETM). Because of high crystallization speed of these materials it is difficult to prepare organic electrophotographic layers of high quality. It is a common fault of these ETM. In this work was prepared ETM with good film forming properties by reaction of 1-(2,3- epoxypropylamino)anthraquinone and 1,3-benzenedithiol. ETM bis[4-(anthraquinone-1-amino)-3-hydroxy-1-thiabutyl]- benzene was obtained this way. The drift mobility of electrons was measured by a time-of-flight method. The transient of a small charge had a fast relaxation but a characteristic kink, by which the time of transit was determined, was weakly expressed because of a strong degree of dispersion of electron transport. The drift mobility of electrons was 4.6(DOT)10^-7 cm²/Vs at an electric field strength 8 (DOT) 10⁵ V/cm and the temperature of 26 degrees Celsius. The photosensitivity of positively charged photoreceptor consisting of the lower photogenerative layer of Y-type titanyl phthalocyanine and an ETM transport layer in the spectral range 600 nm to 860 nm is as high as 80 m²J^-1 to 120 m²J^-1.

Peculiarities of the polarization change of transmitted and reflected light, incident normally to surface of a crystal, are experimentally and theoretically investigated. Such changes in polarization are caused due to anisotropy dielectric constant of crystal which can be either internal property of crystal or arises, for example, due to one- dimensional elastic deformation of a cubic crystal. At the significant absorption coefficient or great thickness L of a crystal the effect of polarization change is observed only for reflected light. Since in strong absorption case the 'active depth' of crystal can be compared with the length of probe wave, for registration of birefringence a special high- sensitivity-polarization-optical technique (HSPO) was worked out. The results obtained for Si and Ge crystals are discussed and qualitative comparison with the theoretical calculations are made.

Correlations due to biexcitons as well as to two-pair scattering states are direct manifestations of Coulomb quantum kinetics. Effects resulting from the memory structure of the corresponding contributions to the optical interband polarization are analyzed taking a ZnSe single-quantum well as model system. Our calculations are based on a microscopic density matrix description using the dynamics controlled truncation scheme for closing the hierarchy of higher-order density matrices. A detailed comparison between experiment and theory allows for the identification of numerous effects directly reflecting different aspects of pair-correlations. In particular, we demonstrate various influences of the two-pair scattering continuum on four-wave-mixing signals. Furthermore, we show that signals with a dynamically changing polarization sensitively monitor a competition between coherent parts of the dynamics and signal components induced by incoherent exciton densities. Surprisingly, the phase of these signals is found to be almost unaffected by the presence of incoherent densities. This result can be traced back to a compensation of the influences on the phases resulting from different incoherent parts of the dynamics. Six-particle correlations representing transitions from incoherent densities to two-pair correlations turn out to be indispensable for a proper description of this effect.

Amplification and generation of microwave radiation by optical phonon transit-time resonance GaN THz maser is investigated theoretically by Monte Carlo simulations. Results confirm that GaN is a promising material for THz power generation. The amplification and generation occurs in the wide frequency range of 0.3 to 3 THz and persists in the THz frequency range up to liquid nitrogen temperatures and doping levels of about 5 X 10¹⁶ cm^-3.

The effect of ultrathin dielectric layers on the reflection of linearly polarized light from transparent or strongly absorbing massive substrate or from an interference film from the viewpoint of optical diagnostics of such layers is investigated. Approximate formulas describing the contribution of ultrathin layers to conventional Fresnel reflectivity for s- and p-polarized light are obtained by the perturbation method. The dependence of the differential reflection on the angle of incidence and parameters of media is analyzed. It is shown that approximate expressions describing the differential reflection can be used to solve easily the inverse problem, in particular, for unambiguous determination of the thickness and refractive index of ultrathin surface layers.

It is shown that the excitation annihilation kinetics of a finite molecular assembly asymptotically approaches the steady state corresponding to the last excitation remaining in the system. The excitation decay kinetics after eliminating the steady state signal reveals the asymptotic dominance of the slowest annihilation mode. The corresponding annihilation time can be easily estimated from the experimental kinetic traces to give a measure of the system size. The annihilation time estimations for the light-harvesting complex LH2, C₆₀ structures and a few poly(arylene vinylenes) are presented.

Probabilities of intra- and intersubband acoustic scattering of holes in uniaxially stressed p-Ge in electric field are calculated. Perturbation of the free hole states by impurity potential is taken into account. Perturbation has a resonant nature and takes maximum values in the region of hole energy around energy position of quasi-local impurity state. Probabilities of acoustic and impurity scattering increase abruptly in that region. Calculated probabilities are used for Monte-Carlo simulation of hole motion in uniaxially stressed p-Ge in strong electric field. The essential influence of intersubband hole transitions with partaking of high-frequency acoustic phonons on the electric current is shown. Comparisons of theoretically obtained current-pressure dependences and experimental ones is performed.

The pressure-dependent behavior of quasi-local impurity states (QIS) induced by shallow impurity centers in uniaxially stressed p-Ge is described theoretically within screened Coulomb potential model. Dependences of energy position and broadening (lifetime) of QIS on pressure are calculated. They differ fundamentally from the results obtained within a short- range potential model. The wave functions of QIS are built. Perturbation of free hole wave function by the potential of a shallow acceptor is obtained analytically. Effective cross- section of impurity scattering of holes with QIS existing in valence band is calculated. Scattering cross-section dependence upon hole energy has a resonant character. The increase of pressure involves a decrease of cross-section values in the resonance region. Anisotropy of scattering cross-section is explained by anisotropy of free hole wave function perturbation in momentum space.

The study of self-diffraction in the Raman-Nath regime through three and four-wave mixing processes related to excitation of surface polaritons at the fundamental and second-harmonic frequencies by means of induced dynamic gratings was carried out. The effects of enhancement and bistability of second- harmonic generation were determined. All these phenomena are caused by the surface enhanced local field due to excitation of surface polaritons and can be used to increase sensitivity of nonlinear optical techniques for surface probing.

Parametric interactions in periodically poled lithium niobate are studied by using 2D non-paraxial finite-difference beam propagation method based on Pade (1,1) approximant of propagation operator and implicit quasi-Crank-Nicholson scheme. The nonlinear perfectly matched layer boundary conditions for non-paraxial beam propagation method are developed and applied to the simulation of parametric spatial solitons. Its effectiveness is verified by way of comparison of different realization of transparent boundary conditions.

This work reviews three methods for determination of various parameters of a layer with defects. The first method involves placing the investigated layer between metal electrodes. However, results obtained by this method are now always reliable. The other two methods employ principles of electrophotography for investigation of layer properties. These methods allow to perform measurements without changing layer properties. Measurements are much faster and more precise than using the first method. The results are repeatable, it is sufficient to perform measurements on a single sample, which is not damaged during the measurements. The second method allows detection of single defects in a layer. This method is used in the case of layers with resistance higher than 10¹⁶ (Omega) per 1 cm² of layer surface. The third method is used to measure properties of layers with resistance higher than 10⁷ (Omega) per 1 cm² of layer surface. The latter method allows easy determination of conditions when layer defects do not affect the measured parameters of the layers. This method is useful for investigation of layers with thickness ranging from a fraction of a micron to several hundreds of microns.

Valence electron momentum distribution functions of ionic oxide Al₂O₃ were investigated using the measured and calculated Compton profiles. Compton lines were measured using the X-ray three-crystal spectrometer. The scattering angle was 155 degrees. Monochromatic AgK and M₀ ((lambda) equals 0,056 nm, hv equals 22,46 keV) radiation was used. Monochromatization of X-ray radiation was achieved by using Ceylon graphite. LiF served as the crystal-analyzer. The measured Compton lines were normalized using noncoherent scattering factors calculated taking into account ionization of atoms. It was found that, although ionic binding predominates in Al₂O₃ crystal lattice, experimental results are best explained by a theoretical model based on an assumption that one of electrons lost by aluminum does not participate in ionic binding with oxygen.

On their way through matter, energetic heavy ions induce a trail of ionizations and excitations. The result of this interaction is the formation of ion tracks consisting of complex damage structures in the lattice (single defects and defect clusters) and irreversible physical, chemical and structural changes. This report gives a short review of the damage creation and the track morphology in various insulating materials. In addition, some selected examples for application of ion-induced modifications will be presented.

The thermally stimulated relaxation (TSR) processes in CaF₂, BaF₂ and LiBaF₃ crystals (X-ray irradiated at LNT or RT) have been investigated by means of the ionic conductivity, thermally stimulated (TS) ionic depolarization current (TSDC), TS current (TSC), TS luminescence (TSL) and thermal bleaching techniques. The ionic TSDC measurements evidence that under DC field fluorides accumulate large ionic space-charge (thermoelectric state is formed) as a result of the migrating anion interstitial and/or vacancy capture on defects. In the ionic conductivity region (290 - 650 K) the thermoelectric state anneals, and several wide and overlapping anionic TSDC peaks are detected. The ionic TSDC stages correlate with the X-ray induced absorption band (F-type and other) thermal bleaching stages. These data evidence that the TSR processes are initiated and controlled by the anion defect thermal detrapping and interaction with the color centers and other localized charges. The anion diffusion-controlled TSR processes take place in fluorides. The TSL, TSC and TSL efficiency (TSL/TSC) data evidence that holes and, probably, the interstitials are detrapped: in CaF₂ -- at 125 - 190 K, 260 - 320 K; in LiBaF₃ -- at 132 K, 170 K and 220 K. The hole or interstitial diffusion-controlled radiative recombination (TSL) takes place above LNT.

The diamond-like carbon films, deposited by direct ion beam deposition method using mixture of C₆H₁₄ and H₂ with and without silicon presence, have been investigated by Raman spectroscopy, X-ray photoelectron spectroscopy, ellipsometry, IR-visible-UV transmission, and electron paramagnetic resonance techniques. The D and G line widths and peak positions, integrated intensity ratio (I_D/I_G) in Raman spectra indicate these films being amorphous, mixture of sp² and sp³ bonds. It has been found that a-C:H films formed while increasing substrate temperature and deposition ion energy tend to be graphite-like. Increasing of hydrogen content in gas mixture made these films more polymer-like with low content of dangling bonds. Traces of silicon increase sp³/sp² ratio. The DLC films on silicon are able to greatly reduce IR reflection.

The effect of gamma-irradiation on the IR optical properties of the ternary chalcogenide glasses (ChG) of Ge-Sb-S system is investigated. The IR optical transmission spectra in the 4000 - 1000 cm^-1 (2.5 - 10 micrometer) region of stoichiometric line (STL) Sb₂S₃-GeS₂ and non- stoichiometric line (NSTL) Sb₂S₃-Ge₂S₃ glass compositions are measured. The compositional dependences of intensity of the main impurity absorption bands connected with the existence of oxygen-, hydrogen- and carbon-containing groups in the glass matrix before and after gamma-irradiation are analyzed.

The influence of gamma-irradiation on the optical properties of Ge_xSb_40-xS₆₀ chalcogenide glassy system is studied. It is established that long-wave shift of the optical absorption edge or 'gamma-darkening' effect in the investigated glasses depends on their chemical composition or average coordination number Z. The maximum gamma-irradiation effect is observed near the point of Z approximately equals 2.67 and it is absent in Sb-rich ternary bulk samples. The gamma-induced changes of the optical absorption are unstable and restores to some residual value after the period of approximately 2 months. The observed features of the gamma-induced effect are discussed in terms of the compositional dependencies of compactness and fraction of chemical bonds, determined according to the ordered bond network model.

The illumination-time evolution and the wavelength dependence of the photoinduced changes in dislocation mobility on the (111) face of C₆₀ single crystals in air for the wavelength range 150 - 900 nm and power densities 0.2 - 2 mW/cm² has been investigated. The results show that the light exposure in air leads to the decrease of the dislocation mobility. The magnitude of the effect as a function of the illumination time was investigated and a two-stage relationship was obtained. The ultraviolet light was found to be more effective than the visible light in the photoinduced reduction of dislocation mobility and solubility. In the wavelength range of 150 - 700 nm, the reduction of dislocation mobility under light irradiation linearly increased with increasing the photon energy. The obtained results are discussed in terms of the photoinduced polymerization, which proceeds through different stages including the formation of dimers, polymer chains and cross-linked polymerized structures.

Combined doping of PbWO₄ scintillation crystals with antimony and ytterbium as well as molybdenum and ytterbium has been carried out and the influence of the doping on optical transmittance, radiation hardness, intensity and spectrum of X-ray excited luminescence has been studied. We demonstrate that simultaneous doping with Sb (100 ppm) and Mo (500 ppm) shifts the band peak of X-ray luminescence from the region 430 - 450 nm to 520 nm and increases the intensity and decay time of the luminescence. The highest luminescence intensity is observed in crystals simultaneously doped with all 3 dopants (Mo, Sb, Y). The origin of the modifications is interpreted by formation of microinclusions of tungstenite phase in doped PWO crystals. The results indicate means for further development of scintillation characteristics of PbWO₄ single crystals in order to effectively utilize the crystals as scintillators in radiation detectors for application in high-energy physics experiments.