The design and operating principle of a pulsed proton source based on a Penning-type reflective discharge with a cold hollow cathode is described. Gas-discharge systems with a small aperture hollow cathode ensure the formation of inhomogeneous plasma with increased density on the discharge chamber axis and in the emission electrode area and are characterized by a relatively low discharge voltage. Such a discharge system fully meets the requirements for plasma generators of charged particle beam sources with high current density. The results of studies on the influence of key parameters of the discharge system: working gas pressure, magnetic field induction, geometry of the hollow cathode on the discharge, and emission characteristics of the source are presented.

The results of study of the behavior of surface plasmon polaritons in the layered structure of a VO2‒SiO2-graphene-based hyperbolic metasurface under the influence of an external magnetic field before and at the beginning of the phase transition of vanadium dioxide are presented. As a result of calculations, it is shown how the isofrequency contour of surface plasmons changes taking into account the different direction of the external magnetic field. It is also shown how an external magnetic field affects the direction of static magnetization caused by the inverse Faraday effect. This work can offer additional ways to control the behavior of surface plasmons, as well as become the basis for the study of new self-adjusting structures.

Pure boron coatings have been deposited on stainless-steel substrates using a planar magnetron with a thermally insulated target of pure crystalline boron in a direct current discharge of up to 50 mA in an argon atmosphere. The magnetron was designed to be used as a component in an electron-ion-plasma test bench for in situ monitoring of boron deposition growth using synchrotron radiation from the VEPP-3 electron storage ring at the Budker Institute of Nuclear Physics of the Siberian Branch of the Russian Academy of Sciences. Using this magnetron, we have fabricated boron films with thickness up to 1.5 μm and studied their surface morphology, mechanical properties, and coating composition.

We describe here the electrode system, design, and parameters of an ion source based on a Penning-type hollow-cathode reflex discharge developed for generation of proton beams. Especially for proton beam generation, a modified geometry of both hollow and reflex cathodes was fabricated. The working gas is molecular hydrogen. Ion extraction and beam formation are performed using a three-electrode single-aperture optical system with a 3-mm diameter emission aperture. At an accelerating voltage of 33-35 kV and a discharge current of 0.55 A in continuous mode, the ion beam current was 15-17 mA, and in pulsed mode, at a discharge current of about 2 A, the beam current was 55 mA. The beam consists mainly of H+, H-2(+), and H-3(+) ions, with the proton (H+) fraction up to 27% in continuous mode and 40% in pulsed mode

Microwave imaging technique allows obtaining images of hidden objects in structures and media using microwaves. Usually in short-range microwave imaging systems, the back-scattered signal is used, when a combined transmit-receive antenna scans over a plane, forming a two-dimensional synthesized aperture, while the signal reflected from the object of observation is recorded, as a result of which a microwave hologram of the object is formed. The second option involves registering the forward-scattered signal, when the transmitting and receiving antennas are located on opposite sides of the object and scan synchronously. The purpose of this work is a theoretical and experimental comparison of these two sounding options, identifying the advantages and disadvantages of each option, taking into account the features that arise when solving various problems of microwave imaging. Keywords: microwave holography, mivrowave image, back-scattered signal, forward-scattered signal, range resolution.

Based on analysis of the specific features inherent in the trajectory of a charged particle moving in an inhomogeneous electromagnetic wave, the physical processes determining the nature of ponderomotive forces are specified. In particular, the reason for switching the accelerated motion of a particle passing through an electrical field with zero amplitude in the direction perpendicular to the electrical field to deceleration with an increase in the electrical field amplitude is detailed. The effect of the inertial mass on the trajectory of a charged particle moving in an inhomogeneous electromagnetic wave is determined.

The features of the probe technique are described and the results of measuring the parameters of plasma generated by a planar magnetron sputtering system with a pure boron target during coating deposition are presented. A feature of probe measurements was the use of heating the collecting surface of a single Langmuir probe. Heating led to a decrease in the electrical resistance of the boron film on the surface, which made it possible to carry out in situ probe measurements of the magnetron discharge plasma parameters during the entire process of boron coating. Keywords: plasma parameters, probe method, planar magnetron, boron films.

This study is devoted to generalization of the traditional approach for the description of photon scattering on free electrons in the case of ultrashort laser pulses. In the framework of the second order of quantum mechanical perturbation theory with the use of the Klein–Nishina formula, we derived an expression for the total scattering probability during the whole time of the pulse action that is applicable in the relativistic limit. The redshift of scattered pulse spectra under an increase in the scattering angle in the relativistic case was studied. The trends of the total scattering probability on the duration of ultrashort laser pulses were categorized.

The paper presents the results of a study of the current-voltage characteristics and optical emission spectra of plasma of a atmospheric pressure pulsed discharge plasma at a frequency of several tens of kilohertz and a pulse duration of up to 10 μs, in the mode of generation of plasma flows containing metal particles. The features of the plasma generator conclude in combination of the design of electrodes, as well as the modes of electric and gas supply of the discharge system. The cathode is a crucible containing a melting insert which allows the discharge operation in a low-current form with a current of 40 mA to 1 A, at a sufficiently high voltage of 150 to 200 V, without transition to arc discharge mode. Such parameters make it possible to generate atomic flows of a melting cathode insert, which are blown out by a jet of working argon gas, pumped at a flow rate of 1 l/min, outside the discharge system. The entry of a metal component into a gas-discharge plasma affects the parameters of the discharge operation, as well as the properties of its optical emission. In the context of this phenomenon, the spectral distributions of the intensity of optical radiation corresponding to the lines of magnesium, indium, and zinc were investigated, as well as their time dependence during the current pulse period operation, in relation to the identification of physical features leading to stable generation of flows of metal atoms at atmospheric pressure.

Представлен сравнительный анализ процессов функционирования и нанесения покрытий вакуумным и газовым магнетроном в частотно-импульсном режиме самораспыления с медной и серебряной мишенями.Осо бенностью проведенных исследований является использование единого устройства, функционирующего при различных давлениях аргона: 2 10-3 Торр и 10-5 Торр.Сравнение характеристик устройства при таких давлени ях и свойств полученных покрытий на поверхности образцов показало

Изучен скейлинг в поведении сопротивления аномального эффекта Холла ρAHE от продольногоρ в нанокомпозитах (CoFeB)x (LiNbO3)100-x с низкой концентрацией диспергированных атомов Co и Fe (Nd ~ 4 · 1020 см-3) в аморфной матрице LiNbO3. Исследования выполнены ниже порога перколяции (xp ≈ 49 ат. %) в диапазоне x ≈ 40-48 ат. %, в котором наблюдается логарифмический закон в температурной зависимости проводимости σ ∝ ln T (x ≈ 44-48 ат. %), переходящий в закон "1/2" ln σ ∝ -(T0/T )1/2 при x ≈ 40-42 ат. %, характерный для со-туннельных процессов переноса в нанокомпозитах. Обнаружено, что в скейлинговой зависимости ρAHE/x ∝ [ρ(x)]n степень n ≈ 0.24 с точностью 5 % совпадает с n в аналогичной зависимости для НК на базе иной матрицы (CoFeB)x(Al2O3)100-x c высоким содержанием Nd ~ 1021-1022 см-3, а также с n в параметрической зависимости ρAHE ∝ [ρ(T )]n для образцов с наименьшими x ≈ 40 ат. %. Обнаруженные особенности связываются с коррелированным изменением вероятности со-туннельных переходов в совокупности из более 3-х центров под действием спин-орбитального взаимодействия. Не исключается также возможность проявления туннельного аномального эффекта Холла барьерного типа на интерфейсах гранул.

In this study, boron thin films were deposited on metal substrates using planar direct current (DC) magnetron sputtering with a pure boron target. Boron has high electrical resistance, severely impeding its application in a magnetron discharge; however, it is a semiconductor and its resistance decreases as the temperature increases. We used a planar magnetron with a boron target that was heated in a DC discharge current up to 50 mA in argon and nitrogen at a pressure of 2-3 mTorr. For these discharge parameters, at a distance of 5 cm from the target the boron deposition rate was about 150 nm/h. Thin boron films with thickness up to 1 μm were obtained and their surface morphology was studied. The deposition technique and the properties of the films are discussed.

A scaling behavior of the anomalous Hall effect resistivity ρAHE versus the longitudinal resistivity ρ in (CoFeB)x(LiNbO3)100 − x nanocomposites with a low content of dispersed Co and Fe atoms (Nd 4 × 1020 cm−3) in an amorphous LiNbO3 matrix is studied in the range x ≈ 40–48 at

The field dependences of the electrical conductivity of Pt/diamond-like carbon (DLC)/Pt structures based on thin layers of high-resistivity DLC are studied. It is shown that the nonohmic behavior of the conductance of structures is described by the Frenkel–Poole formula and is related to correlated distribution of charges under conditions of their percolation hopping transport between low-resistance DLC regions.

Investigation of the processes involved in the synthesis of magnesium oxide and zinc oxide powders using the thermal effects of an atmospheric-pressure glow discharge plasma in an inert gas flow are described. The discharge operates in a repetitively pulsed mode with pulse repetition rate of several tens of kilohertz and pulse duration up to 12 mu s, discharge current of 600 mA and voltage up to 300 V. These parameters lead to thermal erosion of magnesium or zinc inserts in a molybdenum crucible. The chemical and phase composition of the erosion products were determined using TEM/EDS and X-ray diffraction analysis, and the composition of the plasma was assessed by optical emission spectrometry. This experimental approach allows fabrication of powders of these metal oxides with characteristic particle size 10-50 nm, and the formation of coatings of these materials in a one-step process.

Planar magnetrons with a heated crystalline boron target are promising for depositing boron coatings intended for a wide range of scientific and industrial applications. The promotion of this type of magnetrons requires an in-depth investigation of the coating deposition process. A new version of such a magnetron is created for the vacuum electron-ion-plasma (VEIP) test installation for in situ synchrotron radiation monitoring of the boron coating synthesis. The paper proposes the design and parameters for this magnetron and discusses the boron coating deposition using the VEIP test installation.

The features of the probe technique are described and the results of measuring the parameters of plasma generated by a planar magnetron sputtering system with a pure boron target during coating deposition are presented. A feature of probe measurements was the use of heating the collecting surface of a single Langmuir probe. Heating led to a decrease in the electrical resistance of the boron film on the surface, which made it possible to carry out in situ probe measurements of the magnetron discharge plasma parameters during the entire process of boron coating.

In an ion source based on a pulsed planar magnetron sputtering discharge with gas (argon) feed, the fraction of metal ions in the ion beam decreases with decreasing gas pressure, down to the minimum possible working pressure of the magnetron sputtering discharge. The use of a supplementary vacuum arc plasma injector provides stable operation of the pulsed magnetron sputtering discharge at extremely low pressure and without gas feed. Under these conditions, the pressure dependence of the gaseous ion fraction displays a maximum (is nonmonotonic).

В настоящей работе исследован слаботочный разряд (до 1 А) атмосферного давления в режиме импульсного электропитания с частотой от 20 до 100 кГц в потоке аргона с расходом до 3 л/с. Увеличение частоты следования импульсов приводит к снижению напряжения инициирования разряда почти в 2.5 раза, и уменьшению времени фронта тока разряда почти в 2 раза. Данный экспериментальный факт обусловлен возрастанием концентрации возбужденных атомов рабочего газа аргона, смешанных с возбужденными молекулами воздуха в промежутках между импульсами на фоне снижения тока разряда.

The article describes IUHFSE RAS experience in designing MMICs based on gallium nitride heterostructures on various types of substrates: sapphire, silicon and silicon carbide in the frequency range from 10 GHz to 96 GHz. Such as power amplifiers, low-noise amplifiers, and a chipset for radio communications and radiolocation: voltage-controlled oscillators, mixers, multi¬pliers, and transceiver MMIC with integrated antennas. HEMT transistors based on gallium nitride are a suitable for creating a radiation resistant components for frequencies up to 100 GHz.