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This paper describes the model of Poisson's composite compound distribution for photon statistics with regard to their grouping in the Fock, thermal, and many other states. The method of generating functions is used to calculate the distribution of probabilities, moments, and correlation functions. The parameters of the conditional states arising from the subtraction of photons by splitting the beam are determined. The problem of state reconstruction through quadrature quantum measurements is considered. The research is aimed at developing high-precision methods for generating and controlling optical quantum states.

Experiments and simulations are performed to study the formation of silicon nanocrystals (Si-NC) in multilayer structures with alternating ultrathin layers of SiO₂ and amorphous hydrogenized silicon (α-Si:H) during high-temperature annealing. The effect of annealing on the transformation of the structure of the α-Si:H layers is studied by methods of high-resolution transmission electron microscopy, Raman spectroscopy, and photoluminescence. The conditions and kinetics of Si-NC formation are analyzed by the Monte Carlo technique. The type of the resultant crystalline silicon clusters is found to depend on the thickness and porosity of the original amorphous silicon layer located between the SiO₂ layers. It is shown that an increase in the thickness of the α-Si layer in the case of low porosity leads to the formation of a percolation silicon cluster instead of individual Si nanocrystals.

The phase and elemental compositions of GeSi heterostructures deposited on non-refractory substrates are analyzed by using a non-destructive express technique, i.e., the Raman spectroscopy. It is shown that application of pulsed laser annealing allows one to vary the elemental composition and size of nanocrystals formed from solid alloys of germanium and silicon.

The formation of an absorption layer on the Si(111) surface under conditions of sublimation at temperatures of 1000-1100 °C and subsequent quenching at T = 750 °C is studied by methods of in situ superhigh-vacuum reflection electron microscopy and ex situ atomic force microscopy. The distribution of the concentration of adatoms on an extrawide (~60 μm) atomically smooth terrace is determined for the first time, and the diffusion length x_s = 31 ± 2 μm at T = 1000 °C is obtained. The analysis of the temperature dependence of the equilibrium concentration of adatoms near a monatomic step allows pioneering measurements of the energy necessary for the adatom to pass from the step to the terrace E_ad ≈ 0,68 eV. Based on these results, the energy parameters for some atomic processes on the Si(111) surface are estimated.

A Monte Carlo grid model is proposed to describe the formation of semiconductor nanostructures by the vapor-liquid-crystal growth mechanism. This model is used to simulate the growth of GaAs nanostructures by the method of droplet epitaxy in the temperature range from 500 to 600 K in As₂ flows with intensity of 0.005-0.04 ML/s. The morphology of the resultant structures is demonstrated to depend on the growth parameters. Etching of the GaAs substrate by a gallium droplet is studied. The ranges of temperature and As flow rates necessary for the formation of GaAs nanorings are determined. The conditions of the formation of single and double concentric rings are analyzed.

A method is presented to be used in a computational experiment aimed at studying the internal structure of nano-mesoscopic objects, i.e., conducting subsystems and quantum phenomena in solid submicron objects, which demonstrate an individual behavior of low-temperature resistance.

Publications dealing with the study of methods of reducing a three-dimensional problem of the elasticity theory to a two-dimensional problem of the theory of plates and shells are reviewed. Two approaches are considered: the use of kinematic and force hypotheses and expansion of solutions of the three-dimensional elasticity theory in terms of the full system of functions. Papers where a three-dimensional problem is reduced to a two-dimensional problem with the use of several approximations of each sought function (stresses and displacements) by segments of the Legendre polynomials are also reviewed.

This paper describes the study of the influence of a microstructure characterized by directed or chaotic distribution of nanoinclusions and strain rate on the deformability of a nanocomposite. It is revealed that, under identical load conditions, crack formation occurs in nanocomposites whose structural elements are mostly directed in the same way at lower strain rates than in nanocomposites with chaotic distribution of the hardener. It is shown that, as the strain rate increases, the influence of the structural order on the limit deformation reduces due to transition from shear strain to rotational strain. No cracks are formed in bonding metals and nanocomposites by explosion welding. The experimental results obtained in the study of transverse bending of two-layer welded beams and the structure in the vicinity of the weld reveal that the obtained metal - nanocomposite compound has a uniform structure retained in deformation, with fracture occurring in the nanocomposite.

Different approaches to the determination of the carrying capacity of bars and shells under elastoplastic deformation and creep deformation conditions.

This paper presents the results of an experimental study of the elastic and viscoplastic properties of alloys using elastoplastic theory. The need to study complex loading of materials, consider the microstructure evolution during deformation, and develop an appropriate theory of experiment and adequate constitutive relations is highlighted.