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The kinetics of mirrors with saturable absorption is investigated by a pump-probe singlefrequency technique in reflection of femtosecond pulse radiation with the central wavelength of 1040 nm. The double modulation method with probe radiation detection at the summary frequency allows suppressing the scattered pump radiation contribution and reaching the reflection change sensitivity at a level of 10^-5. The kinetics of recovery of the linear reflectivity of the mirror including resonant quantum wells with nanostructured barriers is studied for the surface density of photons in pump pulses of (0.3-5.8) x 10¹⁴ cm^-2. The time of electron-hole recombination (7.8 ps) is found to be appreciably shorter than in samples with quantum wells separated by thick barriers; the time of ionization of excitons localized in quantum wells (0.2-0.4 ps) increases with the pump intensity.

The transformation of zero-order Bessel beams to a second-order Bessel vortex beam in a c-cut CaCO₃ crystal has been studied experimentally. It has been shown that it is possible to control the beam transformation in the crystal during heating. The influence of the thermo-optic effect and the linear thermal expansion of the crystal on the transformation of the Bessel beam is explained.

The possibility of improving the parameters of semiconductor integrated circuits by replacing the silicon layer in a metal-insulator-semiconductor transistors by a material with higher mobility of charge carriers. It is shown that for the totality of properties, germanium is best suited for this purpose. Recent developments in this area made in different laboratories both in Russia and abroad are discussed.

The current-voltage characteristics (CVC) of PbSnTe:In films with a tin content of x ≈ 0.29 at helium temperatures under conditions of unipolar injection from contacts and restriction by a spatial charge in a magnetic field of up to 4 T have been studied. Analysis of the CVC has shown that the observed CVC features change as the magnetic field is increased from 0 to 4 T. The relationship between these features and the presence of a multilevel system of traps located in the band-gap zone is validated.

Negative differential resistance in an UV laser InGaN/GaN diode is demonstrated. Switching between the lower and upper branches of the S-shaped current-voltage characteristic leads to a change in the optical radiation power by six orders of magnitude as the current is increased from 3 to 15 mA.The occurrence of a negative differential resistance is explained by superlinear injection of charge carriers of the same sign into a high-resistivity InGaN quantum well.

A specialized data acquisition system is developed, designed, and fabricated at the Budker Institute of Nuclear Physics of the Siberian Branch of the Russian Academy of Sciences for conducting precision experiments with a CMD–3 detector of the VEPP–2000 electron-positron collider. The structure of electronic hardware is described.

Several facilities for electron-beam welding have been developed and fabricated at the Budker Institute of Nuclear Physics of the Russian Academy of Sciences. A prototype of the system designed for accurate determination of the welded seam position before the welding process and aiming of the electron beam during the welding process is described. For this purpose, the difference in scattering of electrons (and formation of secondary electrons) by the seam and by the surface of the welded workpiece is used, which allows recording the seam image by scanning with a low-current beam. A block diagram of the prototype and basic algorithms of its operation (both tested and proposed for the future) is given. Results of testing and trial operation of the first prototype of the electron-beam welding facility are considered.

A precision magnetometer based on pulsed nuclear magnetic resonance (NMR) is described. This magnetometer measures constant magnetic fields with an absolute error not more than 10^–6 and a resolution of up to 10^–7. The use of modern digital technologies, such as FPGA, made it possible to significantly accelerate and optimize NMR signals. The magnetometer structure is and the signal processing methods are described, measurement errors are analyzed, and experimental data are presented.

A fast meter of the phase difference of two arbitrarily shaped signals at a frequency of 0.2 to 6 MHz is proposed. The device allows measuring the phase difference for the first harmonic with an error of not more than 1° within ~20 μs. The signal frequency and amplitude may vary at a speed of up to 20 MHz/s and 40 dB/sec, respectively. Basic signal processing and phase calculation are implemented digitally in a field programmable gate array. The electronics design features are presented, the signal processing methods are described, and the meter parameters and the results obtained on the physical facility are given.

This paper describes a system for controlling precision high-voltage power supplies at different potentials designed for an electron cooling facility. The issues of architecture choice and reliability during operation at a high potential under conditions of interference and high-voltage discharges are considered. The design structure and hardware and software used in this facility are analyzed.