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The architecture of silicon multiplexers for multielement IR photodetectors is considered. A review is given of industrially oriented developments of linear (1 × 32, 1 × 288, 1 × 576) and matrix (32 × 32, 128 × 128, 160 × 128, 320 × 256) silicon multiplexers for mid- and far-IR photodetectors based on cadmium-mercury-tellurium, lead-tin-tellurium, and multilayer structures with quantum wells. An analysis is made of the temperature resolution of matrix IR photodetectors based on multiplexers with row and frame integration of photo signals using micrometer to deep submicron CMOS technologies. Typical parameters of the multiplexer and some of the infrared photodetectors designed at the Rzhanov Institute of Semiconductor Physics, SB RAS are given.

A device for studying the relaxation dynamics of nonequilibrium capacitance and charge in the mode of nonequilibrium depletion of MIS structures is designed. Methods of measurements were developed that provide a sensitivity of 0.03 pF and 0.02 pC along the capacitance and charge measurement channels with the acceleration time 1.5 µs and 0.7 µs, respectively. The results are obtained with a double amplitude of the test signal of capacitance measurement of ~15 mV and frequency 5 MHz. A mode of measuring the capacitance-voltage characteristics with a scanning duration up to 100 s is implemented.

The dependence of the fluorescence intensity of Cs vapor irradiated by elliptically polarized light resonant with the F = 4 → F = 5 transition on the scanned magnetic field has a complex shape - a narrow dip against the background of a broad peak. It is found experimentally that the dip is due to the small component of the magnetic field orthogonal to the direction of the laser beam. A two-level atom model with degenerate angular-momentum states predicts an order of magnitude lower contrast of this dip. The experimentally observed contrast of the dip can be explained by assuming that due to the low buffer-gas pressure in the optical cell, part of the resonant atoms is able to return to the laser beam without thermalized collisions with the wall of the cell, increasing the contrast. In addition, accounting for all optical transitions of the D₂-line and the optical pumping of the hyperfine-structure components of the ground state is a fundamental point for the interpretation of the experimental results.

Spectra of the cross section of inelastic scattering of electrons (product of the mean free path of inelastic scattering and its differential cross section) are obtained for SiO₂/Si(100) layered structures from experimental spectra of energy losses of reflected electrons with different energies of primary electrons. Computer simulations of the spectra of the cross section of inelastic scattering of reflected electrons for these layered structures are performed with the use of the dielectric function of the film and substrate materials. It is found that the SiO2 layer thickness determined through comparisons of experimental and model spectra agrees with results of ellipsometric measurements.

A possibility of using electric field energy for accelerating solids to significant velocities (1-10 km/s) is considered. A microelectromechanical electrostatic energy converter is used as a capacitive linear actuator, where energy conversion is performed in nanometer gaps, which allows the specific energy density of ~(3-10) J/m² and more to be reached in a single act of energy conversion at clock frequencies of 1 MHz and more. Such parameters allow pumping of electric field energy up to 10-30 MJ with the 1 m² area of the energy converter, with subsequent conversion of this energy to the kinetic energy of object motion. Specific features of the structure of the high-energy-intensity electrostatic energy converter and its operation at high clock frequencies in the regime of acceleration of a slider with a mass up to 10 kg are considered.

The structure of a quasi-optimal device for joint detection and estimation of the position of a moving spatial object observed in an applicative mixture with a random background is studied by statistical synthesis. It is shown that existing algorithms for detecting stationary objects provide only boundary estimates of the detection probability.

Asymptotic properties of a nonparametric estimate of the separating surface equation defined in the space of independent attributes of classified objects are studied. Based on this analysis, the importance of the influence of a priori information about independence of random variables on the approximation properties of the nonparametric decision function in a two-alternative problem of pattern recognition is established.

An algorithm for selecting the optimal sampling frequency of continuous signals based on the information optimality of the time series of samples is proposed. The effectiveness of the algorithm is shown on the example of solving the problem of determining the relative time delay of signals in multichannel transmission based on an algorithm of digital filtering of harmonic filling.

The piecewise continuous (relay) nature of lumped control actions in problems of timeand energy-optimal control of a wide range of distributed-parameter nonlinear objects of engineering thermophysics is established. On this basis, the required programmed controls in a number of practical situations can be found by the proposed algorithmically precise (alternance) method. As an example, which is of independent interest, the problem of optimal control of nonlinear models of induction heating of metal semi-products before subsequent pressure treatment is considered.

The synthesis of automatic extremum seeking systems for a one-channel object whose model can be represented as a series connection of a nonlinear dynamic component and a static quality function with a distinct minimum or maximum is considered. The possibility of extremum seeking by the localization method involving the use of the highest derivative of the output variable of the dynamic part of the object in the feedback is discussed. Depending on the version of implementation of such feedbacks, two main types of extremal systems are distinguished: one-loop systems, in which data on the static characteristic gradient is sent to the controller, and two-loop systems. In the latter systems, it is suggested to use controllers based on the localization method for preliminary stabilization of processes in the internal loop containing the dynamic part. In the external loop, an integral control law is used and motion to the extremum with specified dynamic quality is implemented taking into account the data on the gradient. Modeling shows the features of the extremal systems under consideration.