The effect of geometric-optical wave front reconstruction is investigated. Femtosecond holograms, which demonstrate both diffraction and geometric-optical mechanisms of reconstruction, were obtained. The waveguide variant of the geometric-optical wavefront reconstruction and the ultrashort pulses temporal reconstruction are discussed.

The possibility of quantum holography in the medium of in homogeneously broadened two-level atoms for two-photon regime of operation proposed by A. Rebane is discussed and peculiarities of such holographic process are considered. The experimental scheme for recording of such holograms is suggested. The conditions for realization of quantum holographic process with this scheme are considered. Also, the original approach for quantum holography in homogeneously broadened three-level atomic system using “stopping of light” procedure is proposed and the theory of such process is constructed

It is shown that the high-resolution laser photoelectron microscope with subwavelength-spatial resolution can be used for an absolute values of the two-photon external photoelectric effect measurements with high (a few nm-scale) localization. The spatial distribution of light intensity in the near field is studied by observing the photoelectron projection images of a subwavelength nanoaperture. The imaging electrons are obtained as a result of two-photon external photoelectric effect induced in the aperture formed at the end of an optical fiber by femtosecond pulses of the second-harmonic radiation (410 nm) of a Ti:sapphire laser. The light-field distribution in the aperture is not distorted by any near-by object, which allows the first nonperturbing measurement of such a distribution.

Katzenellenbaum method of cross sections is developed to the calculation of the light field parameters in nearfield microscopy probe. The dynamics of the modes propagation in the narrowing probe is studied when the probe aperture size is less than the wavelength λ of light. The analytical expressions for the modes wave numbers in the taper probe have been obtained, which essentially facilitate the analysis of the field parameters in the probe and allow to save the computing time considerably. The influence of walls inclination corner of the probe on modes amplitudes behavior is determined for the excitation of the probe by the monochromatic light. We demonstrate that the variation of the wall inclination corner can result to essential changing of the spatial field structure in the output probe aperture. Using the cross sections method we have studied the propagation and decreasing of the femtosecond pulse of light with 50 fs pulse duration in the taper probe.

An exact analytical expression for a density matrix of atom + field system is obtained taking into account of the relaxation of photons and frequency detuning (Jaynes-Cummings model with dissipation). The photon mean number, atom population inversion and Fano Q - factor depending on initial states of the field and various parameters of the one-atom maser parameters are investigated.

Examples of Berry’s and WBBZ - (D.Wojcik, I.Bialynicki-Birula and K.Zyczkowski) quantum fractal constructions are considered. The behavior of fractal dimensions of these very special superpositions of basic states of a particle in a potential box and harmonic oscillator is investigated in going from coordinate representation to momentum and coherent state representations. The mean value of quanta and dispersion for isolated quantum harmonic oscillator prepared in “fractal” state and interacting with another oscillator are calculated.

Dynamics of spontaneous decay and corresponding emission spectrum are exactly treated for a system of two identical two-level atoms in 1D. Just a one-dimensional case is considered in order to maximally extract an information on mutual influence of spatially remote atoms through the radiation field. As a result, an effect is revealed and considered in detail that there exist stable (metastable) entangled states at definite distances between the atoms. That state is supported by a (quasi)stationary field bounded between the atoms. Also, a correspondence is established between the lifetime and emission spectrum, and possibilities for observing the effect are discussed.

On the basis of the master equation for the density matrix the dynamics of the collective spontaneous radiation of two Λ - type three-level atoms interacting with two modes of quantum electromagnetic field in the damped cavity has been considered. The behaviour of the photon numbers in modes has been investigated in the case when both atoms are in excited state at the initial time.

The distinctive features of the propagation of the two-component electromagnetic pulses in an anisotropic media are studied in the frameworks of the system of equations of the resonance of long and short waves. It is shown that an interaction of the light with the quantum systems, which have a constant dipole momentum nonequal to zero, occurs not only in the usual mode of the self-induced transparency, but also in two new modes. In the first one (supertransparency), the pulse propagation causes the significant change of the population density of quantum levels, while its group velocity remains close to linear one. In the second mode (extraordinary transparency), the group velocity of the pulse changes significantly, but the population of the levels is practically invariable. It is also noted that the largest change of the population takes place, if the carrier frequency of the solitons is less than the resonant frequency, at that the detuning value depends on the duration of the pulses.

Nonlinear propagation of longitudinal-transverse acoustic pulses in the system of resonant paramagnetic impurities is theoretically investigated. It is shown that under domination of transversal pulse component and propagation along external magnetic field is realized a regime of acoustic self-induced transparency. At the opposite limit realized new soliton mode, following by propagation velocity decrease, similar to the case of self-induced transparency. At that, however, populations of quantum Zeeman sublevels stay practically unchanged, and transversal component of the pulse suffer phase modulation.

In 1993, C.H. Bennet et. al. had proposed the protocol for quantum teleportation of unknown quantum state. Now, this phenomenon was observed experimentally and numerous applications in quantum telecommunications and informatics are proposed. This method of communication is not direct because it uses classical besides quantum channel. We propose here another scheme where protocol can be established before information transmission and then information is transmitted through quantum electro-dynamic channel of interaction between particles with entangled states. With that, parametric interaction between photons is implemented for coupling of information to this interaction channel and subsequent read out of information. In this scheme, the pair of photons with entangled polarization states is used and parametric interaction trough the field of virtual photons serves as interaction channel.

There is an interest in consideration of the propagation of the Gaussian monochromatic light beams through a cell filled with the medium of two-level atoms (in our case, the atomic potassium vapor), which has (at small detuning from resonant transition to low or high frequencies) the refractive index other than unity (n > 1 for v < v₀₁ and n < 1 for v > v₀₁, where v is the light frequency and v₀₁ is the resonant-transition frequency). In this case, the properties of the radiation passed through the cell are changed. In the very close proximity of the resonance, the nonlinear processes (the three-photon electronic stimulated Raman scattering (SRS) and the six-photon parametric scattering (SPS)) play a crucial role. It is precisely these processes in the two-level medium that determine the irreversibly transformed spectral and angular structure of the light beams at the output of the cell.

The dynamics of free and optically induced decay of quasi-one-dimensional atomic Bose-Einstein condensates (BECs) is considered. The main characteristics of BEC modulation instability were found and compared for the cases of local and non-local interatomic interaction potential. The dynamics of BEC decay was studied numerically for the cases of positive and negative scattering length, absence or presence of optical standing wave, and for different shapes of initial BEC density distribution.

We study the interaction of a Bose-Einstein condensate in an optical lattice with additional electromagnetic fields under Raman resonance condition. System of evolution equations describing ultra-short optical pulse propagation and photo-induced transport of cold atoms in optical lattice is derived. The steady state solution of these equations was found. There are new kinds of polaritonic solitary waves propagating.

The semiclassical theory of coherent optical effects observed in a Bose-Einstein condensate (BEC) of a dilute sodium vapor is proposed. They are superradiant scattering of light from BEC, amplification of the probe light pulse under pumping BEC by more power dressing pulse, amplification (by bosonic stimulation) of coherent atomic waves in BEC (atomic laser), light speed reduction in BEC under electromagnetically induced transparency.

A semiclassical theory of superradiant scattering of laser light from Bose-Einstein condensate of dilute gases, taking into account the multimode structure of emitted radiation is presented.

The scattering of the extended in time laser pulse from Bose-Einstein condensate of elongated form is considered. The evaluation of the conditions determining the transition from the usual isotropic Rayleigh scattering to the sharply anistropic (directed along the condensate) cooperative or superradiant Rayleigh scattering is presented

Architecture of a laser digital vector-matrix multiplier based on photon echo was examined for one-way computer scheme. It was found that all operations with qubits (include one-qubit measurements or projection) involved in the algorithm could be realized in frame of nonlinear optical technology.

The schemes of experimental implementation of quantum gates on the states of the individual quantum particle with eight non-equidistant energy levels are presented. The implementation schemes of NOT, controlled-NOT, SWAP, controlled-controlled-NOT, controlled-SWAP, Hadamard gates on the states of quadrupole nuclear with spin 7/2 are given.

The equal spin-spin interactions model is considered for development of the schemes of experimental implementation of universal set of gates, which is sufficient to construct the quantum algorithms of arbitrary complexity. This model is am imitation of the spin-system of the real molecule of a nematic liquid crystal, where the NMR spectrum with many resonance lines was observed. This system seems to be very perspective for quantum informatics.

We have observed numerically a quantum mechanical probability current echo response generated by an ensemble of the drops of Bose-Einstein condensates (BEC) loaded in the cells of optical dual lattice. Echo was excited with the pulses of two-photon optical radiation due to Raman scattering. Echo temporal form and the role of inhomogeneous broadening are discussed.

A generalization of the Bloembergen-Shen model was supposed on cases those Raman active molecules with an arbitrary number of normal modes. On the basic of this model were investigated Raman echo signal characteristics when medium was excited by pulses of widths up to one period of optical oscillations. It was shown that a large number of echo responses on Stokes and anti-Stokes components could arise even under a two-pulse action in a continuous monochromatic pumping field. The number of echo responses depended on the number of molecular normal modes and the geometry of experiments. At small exciting pulse “areas,” the echo responses whose Stokes and anti-Stokes components corresponded to normal vibrational modes of a molecule.

A four-level model, involving the ground, one-exciton and two-exciton states as well as a high-lying molecular term through which the two-exciton state annihilates, is used for analyzing the bistable optical response of a thin film built up of oriented molecular aggregates. We focus on the effects of inhomogeneous broadening of the exciton optical transitions and exciton-exciton annihilation on bistability of the thin film response. It turns out that the inhomogeneous broadening, preventing generally the occurrence of bistability, may be suppressed considerably due to a fast exciton-exciton annihilation.

The paper is devoted to the phenomenon of a long-lived photon echo (LLPE). The graphical method of calculation of optical echo signals in multilevel systems is developed. Using developed method the formation of LLPE signals in Van Vleck paramagnets is investigated.

Quaternion algebra is offered as the mathematical formalism of dynamics of interaction of a two-level quantum system with an electromagnetic field. Condition of two-level atom, densities operator, Bloch vector, “gyrating moment” vector are considered as the elements of a one-dimensional vector space of quaternion H¹, i.e. are represented as quaternion. Bloch equations in a quaternion formalism are noted. Solution method of the differential quaternion Bloch equation is obtained.

Mathematical formalism of photon echo exciting at interaction of two-level quantum system with an electromagnetic field within the framework of quaternion algebra is offered. The rotation quaternion is used instead of density operator for representation of interaction dynamics of an exterior field with two-level atom, where the components of rotation quaternion are the coordinates of Bloch vector. Liouville fon-Neumann equation for density matrix evolution is substituted by the differential quaternion equation in a quaternion model. The expression for rotation quaternion appropriating to an unitary operator of rotation in matrix representation is obtained. It is shown that the solution of the differential quaternion equation does not require the difficult mathematical operation connected to an evaluation of an exponent from a matrix. The expression for a quaternion superoperator is obtained.

This work is dedicated to investigation the properties and opportunities of photon echo with the purpose of development the physical principle of embodying the optical evaluations on a superposition state of the group of excited particles of resonant gas, which could serve as a basis for increasing of features of quantum information processing regime which is supposed in work. One of the possible physical representations of a quaternion in the signal of photon echo is offered. The principle of the optical echo-processor operation is described to fulfill the operations with quantities which are introduced by quaternions. The example of optical transformation of quaternion quantity in the optical echo-processor is given.

The effect of the rotating of the photon echo polarization vector is offered for a construction of the opto-electronic current transformer. As an active medium that allows get the photon echo the vapors of molecular iodine are used. The theoretical model of the opto-electronic current transformer is discussed. The results of investigation of photon echo (PE), excited by complexly coded laser pulses in molecular Iodine vapors under action of the homogeneous longitudinal magnetic field are given in this work. The recording possibility of special information by exciting pulses on a pair of quantum levels of resonant gas (molecular Iodine vapors) in technique PE is shown experimentally. In this shown experiment the information has two by two values of two relevant features and is represented by the amplitude-time shape and direction of linear polarization vector of radiation. The possibility of using the detected features of formation PE under the action of magnetic field for development the physical principles of the quantum control and for optical information processing introduced by hypercomplex number - quaternion - is shown.

It is shown that inhomogeneous broadening in induced superradiance not only increases the delay time and attenuates the superradiance pulse intensity as well as decreases the period of the cooperative exchange between forward and backward waves in a sample. As a result, it may change the regime of predominance of the transmitted or reflected wave. Also the inhomogeneous broadening leads to decaying of exchange.

The possibility of amplification of pulses of squeezed light in the regime of triggered optical superradiance is analyzed. The kinetic equations are obtained which describe the dynamics of cooperative development of the population inversion and dispersion of the quadrature components of polarization of optical centers interacting with the triggering-pulse field in the squeezed vacuum state. The dependence of the squeezing degree of the superradiance field on the squeezing degrees of the triggering-pulse field and polarization of an amplifying medium is determined. It is shown that in the case of a sufficiently strong squeezing of the medium, the intensity of the squeezed quadrature component of the superradiance signal is lower than that of an incoherent spontaneous background. Therefore, the superradiance field can be characterized not only by a classical squeezing (when the dispersions of quadratures are not identical) but also by a quantum squeezing (when the dispersion of one quadrature is smaller than its vacuum value).

We report the results of detailed investigation of optical superradiance (SR) in LaF₃:Pr³⁺ crystal resonantly excited on the ³P₀-³H₄(0) transition by laser pulse. When the power of the pumping pulse was higher than a certain threshold, the resonant medium emitted by optical SR pulse on ³P₀-³H₄(0) transition in the direction of the pumping pulse (as well as in the opposite direction) delayed in time with respect to the pumping pulse. Further increasing of the peak power of the pumping pulse led to the observation of SR on the ³P₀-³H₆(1) transition also. Thus, the two-color SR in the employed crystal was observed.

Nonlinear propagation of ultrashort (carrierless) electromagnetic pulses in a KDP-type ferroelectric in the system of tunneling transition is theoretically investigated. It is shown, that interaction of the electromagnetic field of pulse with tunneling transition lead to defocusing of pulse. The role of diffraction was looked. The critical parameters of pulse were defined.

The account of the diffraction, influencing on propagation of a pulse duration of few cycle of light oscillations in isotropic dielectric is carried out. The approach includes a method of analytical continuation of dispersive parameters on a complex plane and the average variational Ritz-Uizem principle.

Numerical researches of the three-level atomic system on supervision of pulse and spectrum dynamics of superfluorescence are carried out at incoherent pumping depending on nonradiation relaxations, on influence of phase relaxations are shown. Pulse and spectrum dynamics of induced superradiation depending on the area and duration of input pulse at incoherent pumping, with and without taking into account phase relaxations, are investigated. Depending on media parameters different modes of induced superradiation are researched.

For the known, experimentally realized conditions, the detailed analysis of the field-induced transparency and formation of exceptionally low group velocity of probe light is performed. The secondary fields being due to the atomic polarization induced by the two propagating light pulses - coupling (or dressing) and probe ones, resonant to the adjoining transitions in a three-level scheme, are explicitly taken into account. Partly linear (relative to the probe pulse field) and completely non-linear regimes are considered. Particularly, the outputting coupled wave is shown to be slightly amplified, when the probe light pulse “disappears” inside the medium.

We took into account the generation of high-order Stokes and anti-Stokes forward and backward components in our method of anti-Stokes generation at stimulated Raman scattering in a medium exhibiting variations of the third-order nonlinearity along the direction of propagation. The dependence of anti-Stokes generation efficiency on pump and Stokes input intensity and pulse durations for hydrogen were studied. The results of our research can be used for creation of new effective nonlinear-optical frequency converters and Raman amplifiers.

Relying on the Peres-Horodecki criterion, we investigated the dynamics of appearance of the stationary entanglement in the system of two two-level atoms decaying in the field of common thermostat. We took into account their dipole-dipole interaction and the difference between their atomic frequencies. It was established, that in the absence of the dipole-dipole interaction the presence of the stationary entanglement has a strong dependence on the identity of atomic frequencies. The difference between them (due to their different locations in the crystal or thermal movement), leads to a disappearance of the stationary entanglement. Also we found the dependence of existence of the stationary entanglement from a correlation between the constant of the dipole-dipole interaction, the resonance wave shift and the constant of interaction with the thermostat field - it comes into existence only when the latter value becomes greater than the former ones.

The quantum aspects like entanglement, photon-phonon number distribution function and tomograms of the stimulated Raman scattering (SRS) process are studied using the simplest model of two-dimensional oscillator with quadratic interaction.

The two-mode even and odd coherent states and two-mode squeezed correlated state are discussed. Photon distribution functions, means, dispersions, Fano factor for even and odd coherent states and squeezed correlated state are calculated. The photon distribution function for two-mode squeezed correlated state is obtained. The tomograms of two-mode even and odd coherent states and squeezed correlated states are investigated within the framework of a sympletic tomography scheme. It is shown that the phenomenon of entanglement appears in the system. Two different measures of entanglement are employed.

A set of protocols for teleportation of entangled states and multiqubits dense coding using quantum channels of the GHZ and W type are considered.

A method of magnetic field measurement in plasmas, based on the coherent population trapping effect, was proposed and experimentally tested in a glow neon discharge. Both the strength and the orientation of the field can be determined with high resolution. A particular application to assessment of magnetohydrodynamic stability in electron-cyclotron resonance sources of multicharged ions is theoretically considered. Theoretical estimates show that parameters of plasmas in these sources satisfy the conditions at which the diagnostic works.

In a Y₂SiO₅:Pr³⁺ crystal characterized by two non-equivalent Pr³⁺ optical centers, the interaction mechanisms between Pr³⁺ ions as well as between Pr³⁺ ions and a crystal lattice have been studied. It has been shown that along with the electron-phonon interaction, the interaction between Pr³⁺ ions and two-level systems made an additional contribution to the homogeneous linewidth of the ³H₄↔³P₀ optical transition. Two different mechanisms of the Pr³⁺ interionic coupling have been found. The first mechanism is associated with a dipole-dipole interaction between non-equivalent Pr³⁺ optical centers, while the other one is governed by a cooperative cross relaxation of the excitation energy among the same type Pr³⁺ optical centers.

The effect that may be exerted by an interatomic near dipole-dipole interaction upon optical transient processes in dense resonance media is analyzed. The behavior of the macroscopic polarization after a one-pulse excitation of a dense ensemble of two-level atoms is considered. It is shown that the free polarization signal is of oscillatory nature, with the oscillation frequency varying in time and being dependent on the dipole-dipole interaction constant, the intensity and duration of the exciting pulse, and the detuning of its carrier frequency from the resonance. The free polarization signal decay, which depends on the magnitude and sign of the sum of the detuning of the exciting pulse carrier frequency from the resonance and the Lorentz frequency, may obey either a power or an exponential law. The signal decay rate is determined not only by the inhomogeneous broadening, but also by the ratio of the above parameters. The peculiarities of echo-responses under one- or two-pulse excitation conditions are studied.

The article is devoted to photon echo detection in molecular iodine vapors cooled under supersonic jets. This phenomena could be used in spectroscopic diagnosis of the jets. The methodic, results and the possibilities of their practical application in the development of the optical echo-processors are discussed.

Femtosecond electron-vibrational dynamics in a gas of diatomic molecules pumped by single-photon quantum field is theoretically investigated on the basis of the femtosecond pump-probe spectroscopy technique. The developed theory is applied for calculation of luminescence signal in a gas of Na₂ molecules and it is found that that there is a strong dependence between the form of the temporal spectrum of the signal and the optical density of the medium.

In this paper we consider a numerical differentiation algorithm based on the continuous wavelet transform for improving resolution of composite spectra. This approach provides the best contrast in differential curves compared to the conventional derivative spectrometry. A main merit is that the wavelet-based technique gives stable estimations of derivative without using the regularization, on the other hand, it does not make peak shifts. A comparative study of conventional derivative spectrometry based on the statistical regularization method and wavelet-based derivative spectrometry is made. Examples of the application of these for improving resolution of synthetic composite bands and real-world composite ones coming from molecular spectroscopy are given.

Before it is difficult to say about a peak shape without conducting additional research. Conventional nonlinear fitting methods based on the OLS approach are unsuitable to unambiguously assign the overlapped peaks. This implies that a composite band can be decomposed into elementary components of a given shape with the same integral reconstruction error with a large number of ways. A main drawback of this approach is the high variance of the spectral parameters to be estimated. This is due to the overlapping of individual components, which leads to the ambiguous fitting. In this paper we develop a simple mathematical tool in terms of fractional derivative (FD) to determine the overlapping peaks spectral parameters. It is possible due to several positive effects of FD connected with the behavior of its zero-crossing and maximal amplitude. For acquiring a stable and unbiased FD estimate we utilize the statistical regularization method. Along with the well-known distributions such as Lorentzian, Gaussian and their linear combinations the Tsallis distribution is used as a model to correctly resolve overlapped peaks. As exhaustive examples demonstrating a power of the method we estimate unresolved bands spectral parameters of synthetic and experimental infra-red spectra.

Internal rotation of 1,2-diphenylethane has been studied. Infrared absorption spectra of 1,2-diphenylethane in crystalline phase, liquid and solutions at various temperatures have been investigated. Assignment of the peaks to trans and gauche conformations was performed. Band fitting and factor analysis were applied to conformationally sensitive regions of the spectra. Enthalpy and entropy differences of the conformers were determined and discussed in frames of the reaction field model.

It is established that the photovoltaic effect may occur in centroantisymmetric antiferromagnets. The direction of the photovoltaic current is shown to be governed by the crystal symmetry, the orientation of the antiferromagnetic vector about the crystallographic axes.

The photophysical properties of some new and also some known complex organic molecules emission and generated radiations in the wavelength interval ▵λ^max _osc,fl ≈ 340-760 nm have been studied in a wide range of organic solvent. Specifically, these molecules are based on phenyl-, furyl-, thienyl-oxazoles and oxadiazoles to compile a quasihomological series. Using the measured values of the extinction (ε^v_abs), the fluorescence quantum yields (γ _fl), and the fluorescence lifetime (τ _fl), we calculated rate constants for radiative decay (k _fl), and intercombination conversion (k_ST), along with the cross sections for absorption (σ^max₁₃), and stimulated emission of radiation (σ^osc₃₁). We also found the longest limit pump-pulse rise time (t_lp) for which generate of the oscillations active molecules. Within the framework of the method of spectral-quantum-chemistry modeling LCAO-MO CSF CI INDO/S, CNDO/S, and PPP/S of structure and optical and nonoptical properties for the multiatomic molecules.

Here the photochemical properties of CaF₂ crystal doped by Ce³⁺ and Yb³⁺ ions under pumping with ultraviolet (UV) irradiation resonant to the Ce³⁺ ion interconfigurational 5d-4f transitions were studied and significant codoping effect on the crystal solarization suppression was observed. The photodynamic processes model occurring in the active medium and which taking into account the color center formation and processes of enhanced free charges recombination via valence change of variety of impurity centers was proposed. This model allows to explain both electronic and hole types color centers suppression in Ce:CaF₂ sampels codoped by Yb³⁺ ions. It was shown that Yb³⁺ ions in the crystal act as centers of electron and hole recombination with probability dependent on the extra charge compensation type. Therefore the proposed antisolarant mechanism of the coactivation effect satisfactorily describes photochemical properties of fluorite and other crystal hosts.

Opportunities of laser tests as a powerful and unique research tool of active medium fundamental properties directly in real laser operation conditions for variable intracavity losses are discussed. New technique of laser experimental data interpretation was developed and applied to the analysis of laser tests results for the series of Ce³⁺:LiYb_xLu_1-xF₄ single crystals. Contribution coefficient into total pump-induced intracavity losses of ESA from upper laser level of Ce³⁺ ions and CC absorption at the laser wavelength was estimated. Basic parameters relevant to laser action performance were defined: Ce³⁺ ions ionization cross-section by pumping radiation and Ce³⁺ ion ESA at the laser wavelength, CC absorption (ionization) cross-section at the both pumping and laser radiation wavelength, life-times of transient and long-living color centers, stimulated emission cross-section and relative values of pump-induced free-charges trapping rate by host lattice defects and their corresponding recombination rate.

The spectral-kinetic characteristics of Ce³⁺ ions doped Na₄Y_6-xYb_xF₂₂ (x=0-0.05) single crystals were studied. Ce³⁺ ions 5d-4f interconfigurational fluorescence quantum yield versus Yb³⁺ ion codopant concentration was measured. Pump-induced color center absorption spectra were studied and the efficiency of Yb³⁺ ions codoping antisolarant crystal-chemical technique applied to Na₄Y₆F₂₂:Ce³⁺ was demonstrated. The optimal Yb³⁺ ions content from the point of view of effective tunable laser action was estimated. The obtained results allow proposing Na₄Y_6-xYb_xF₂₂ as a new prospective photochemically stabilized material for UV/VUV application.

Laser-spectroscopic studies of polymeric laser-active media based on Rhodamaine 6G dye incorporated into modified Methylmethacrylate with Methacrylic Acid copolymer samples had been carried out. Absorption and luminescence spectra together with luminescence quantum yield were studied. The basic parameters of the laser oscillation and their stability were obtained. The new potential photostabilizator azotes- and sulphurs-containing organic compounds - Thiourea and Thiazol aromatic derivatives was specially synthesized and their role to dye and polymeric host photochemical stability were studied. In this paper it was shown that these synthesized compounds indeed are high effective photostabilizators. Also it was demonstrated that using of these additives leads to significant increasing of laser action efficiency, from one hand and to rising the working characteristics (operational lifetime) of solid-state laser-active media based on the new synthesized polymer composition materials, from other hand.

Several schemes are considered for the construction of radiation balanced and self-cooling lasers in continuous and pulsed regimes of operation. The formula is obtained for the photon number in the generation field of self-cooling laser with direct. Its intensity of radiation and conditions for its realization are determined. The effect of self-cooling is considered for laser with up-conversion energy transfer. Scheme of radiation balanced with induced cooling is proposed and time of such cooling is estimated. Advantages and drawbacks of proposed schemes are discussed in comparison with traditional laser scheme.

The loss mechanism to account for the loss of laser photos from the cavity due to absorption by the second dopant inside the laser rod is investigated. We introduced a system of three-level ions as a dissipative subsystem and considered that photons can be lost through their coupling to this quantum subsystem. The conventional quantum laser theory is then expanded for this special case.

We studied the resonance fluorescence of Moessbauer radiation of Fe⁵⁷ nuclei with coherently coupled nuclear sublevels. The obtained results prove that the traditional Moessbauer spectroscopy in scattering geometry is effective enough for experimental investigation of the quantum interference of gamma transitions and for studying the coherencies induced by external radiation fields.

The formation of γ-avalanche in the medium with ¹⁷⁸Hf isotope has modeled through the nuclear diffraction channel. The equation system describing the process under two-wave Bragg diffraction conditions has obtained. The numerical simulation for the “optical” thick medium has been made.

The nuclear superfluorescence in the “optical” medium with ¹⁷⁸Hf in propagation channel has been modeled. The general equations system describing the nuclear superfluorescence in the “optical” medium has obtained. The numerical simulation in the propagation channel in the “optical” thick medium with ¹⁷⁸Hf has been made.

Nuclear forward scattering (NFS) of synchrotron radiation (SR) is theoretically modeled into multilevel “gamma-optical” paramagnetic media with effective integer spin (S=1, 2) under the electron spin fluctuations in the unclosed electron shell of Moessbauer ion ⁵⁷Fe⁴⁺⁽²⁺⁾. The equilibrium fluctuations of effective spin is changing the time phase coherence within the total resonant forward scattering amplitude of a gamma-quantum of SR pulse into the Moessbauer nuclei ensemble of a sample. As a result the specific temperature dependence of the resonant response of “gamma-optical” paramagnetic medium takes place.