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The original research results for thin disordered HTSC films based on YBCO are presented in this article. Several experiments have been carried out to confirm a theoretical prediction that the s-phase of superconducting pairing in disordered d-type superconductors can occur with a gradual decrease in the mean free path. The YBa2Cu3O7 – x films are used as samples which possess a d-type of superconducting state that was experimentally confirmed. A gradual decrease in the mean free path was achieved by both thermal annealing and ion irradiation. The experiments included measurements of temperature dependence of the London penetration depth λ and resistive studies.

The goal of this work is the qualitative and quantitative interpretation of experimental data obtained for the effect of additional boron ion implantation on the temperature dependence of dislocation-related luminescence (D1 line) of self-implanted silicon. This goal is motivated by the need in development of effective light emitter for silicon-based optoelectronics. The model explaining the previously established improvement of the D1 line temperature dependence is suggested and supported by computer calculations based on a set of kinetic equations taking into account the radiative and nonradiative electron transitions between energy levels.

The unicity of Shukshin’s oeuvre is that from the middle of 1960s when he is consciously seeking for and invents coding tools of his creations. The author himself has pointed out some methods of «code» creation. He pays attention to the “change of emphasis”, “hints”, “nuances”, things which are said at a glance, cursorily, on parts of text which appear to be secondary. The actual problems, questions, node of the conflict and the conflict itself can be described by Shukshin in one creation, but the extension, comments, answers or the variant of the pay-off are described in another one, which is published many years after. That is why there are a lot of double characters, double episodes, story- lines, which stand in the inter decoding position. So everything that is about author’s code should be considered as the main thing as the author directed to us. The aim of such art strategy is to tell the truth about the time, to state the hate and revolt. This article is about the methods, which Shukshin used, while coding the novels “Director”, “Rhetorical device” and “Order”, and also about clearing up the point of this code.

The results of determining the energy levels of boron-doped silicon implanted with gallium ions by impedance spectroscopy are reported. In the as-implanted sample the boron level remains the same and a second level appears close to the Ga-level reported in literature. In the sample annealed at 1000 °C, two levels are observed neither of which corresponds to the literature values for boron and gallium. It is assumed that in the as-implanted sample this method detects levels of gallium atoms located at a depth where ions penetrate due to the channeling effect, since a large concentration of defects at shallower depths does not allow detection of energy levels due to the Fermi level pinning. Explaining the results for the sample annealed after implantation requires additional research. The main result of this work is to establish the possibility of detecting impurity levels in ion-implanted silicon by impedance spectroscopy even in the absence of subsequent annealing.

The composition and structure of silicon surface layers subjected to combined gallium and nitrogen ion implantation with subsequent annealing have been studied by the X-ray photoelectron spectroscopy, Rutherford backscattering, electron spin resonance, Raman spectroscopy, and transmission electron microscopy techniques. A slight redistribution of the implanted atoms before annealing and their substantial migration towards the surface during annealing depending on the sequence of implantations are observed. It is found that about 2% of atoms of the implanted layer are replaced with gallium bonded to nitrogen; however, it is impossible to detect the gallium-nitride phase. At the same time, gallium-enriched inclusions containing ∼25 at % of gallium are detected as candidates for the further synthesis of gallium-nitride inclusions.

We report the effect of disorder on superconducting phase transition of YBa 2 Cu 3 O 7 − x epitaxial thin films in external magnetic fields. The disorder was produced by several successive acts of oxygen ion implantation. Controlling a total accumulated dose of implanted ions nD, we carried out transport measurements in ab-plane for temperatures T below 91 K and external magnetic fields H up to 11 T. Temperature-field dependencies of in-plane resistivity allow us to analyze H − T phase diagrams for primary compound as well as for disordered structure. Considering the upper critical field Hc2 as the magnetic field which corresponds to a local resistivity drop at the onset of superconducting transition, we found out the following results. By gradual increasing of nD, the phase-transition line Hc2(T) suffers an unconventional critical-field slope reduction, while larger defect concentrations usually enhance the upper critical field in the vicinity of Tc0. Besides, for rather large nD, the curvature of Hc2(T) becomes upward for temperatures close to Tc0. Theoretical interpretation of the experimental data is developed in the framework of linearized Ginzburg-Landau theory with an inhomogeneous superconducting coherence length. A simple expression for the critical temperature Tc is obtained: T c = T c 0 ( 1 − h + α h 3 / 2 ) , where h is the dimensionless magnetic field and α is a constant which describes the defects in a specimen. The formula nicely fits our experimental results.

The formation of a topological structure in thin films of the high-temperature superconductor YBa2Cu3O7–δ (YBCO) using ion implantation is studied. The crystal structure and electrical properties of the initial film and the formed insulating regions are investigated. The critical temperature and critical current are measured for microbridges with a width of 3–50 μm fabricated by ion implantation. The results indicate the effectiveness of the ion-implantation method for manufacturing topological structures in YBCO films.

In this paper, the analysis of the possible replacement of existing multistage membrane and reciprocating compressor units with a set of slow-speed long-stroke compressor stages is carried out. The possibility of replacing the existing multi-stage membrane and reciprocating compressor units with slow-speed stages, taking into account the weight and size parameters, as well as such advantages as durability and improved parameters of vibration characteristics is shown.

3D Monte-Carlo algorithm and computer code have been developed that allows choosing and optimizing the conditions of ion irradiation needed for the adequate ion-beam simulation of radiation damage under fast neutron irradiation. It is established that, by the proper selection of energy and dose of Si+ ions, it is possible to reproduce well the effect of irradiation with fission neutrons of subsurface and buried layers of silicon or Si-based 2D and 3D-heterostructures. The results can be used for testing the radiation hardness of silicon-based electronic and optoelectronic device structures.

The study is concerned with the effect of the additional implantation of Si samples with C+, O+, B+, P+, and Ge+ impurity ions followed by annealing at 800°C on the behavior of the dislocation photoluminescence line D1, induced in the samples by implantation with Si+ ions at a stabilized temperature followed by annealing in an oxidizing Cl-containing atmosphere. It is established that the intensity of the D1 line strongly depends on the type of incorporated atoms and the dose of additional implantation. An increase in the D1 line intensity is observed upon implantation with oxygen and boron; at the same time, in other cases, the D1 luminescence line is found to be quenched. The mechanisms of such behavior, specifically, the role of oxygen and its interaction with implanted impurities are discussed.

Luminescent and structural characteristics of SiO2 layers exposed to double implantation by Si+ and C+ ions in order to synthesize nanosized silicon carbide inclusions have been investigated by the photoluminescence, electron spin resonance, transmission electron microscopy, and electron spectroscopy methods. It is shown that the irradiation of SiO2 layers containing preliminary synthesized silicon nanocrystals by carbon ions is accompanied by quenching the nanocrystal-related photoluminescence at 700–750 nm and by the enhancement of light emission from oxygen-deficient centers in oxide in the range of 350–700 nm. Subsequent annealing at 1000 or 1100°C results in the healing of defects and, correspondingly, in the weakening of the related photoluminescence peaks and also recovers in part the photoluminescence of silicon nanocrystals if the carbon dose is less than the silicon dose and results in the intensive white luminescence if the carbon and silicon doses are equal. This luminescence is characterized by three bands at ∼400, ∼500, and ∼625 nm, which are related to the SiC, C, and Si phase inclusions, respectively. The presence of these phases has been confirmed by electron spectroscopy, the carbon precipitates have the sp3 bond hybridization. The nanosized amorphous inclusions in the Si+ + C+ implanted and annealed SiO2 layer have been revealed by high-resolution transmission electron microscopy.

Ion implantation is a convenient tool for synthesis of silicon nanocrystals in SiO 2 matrix which exhibit strong red/near-IR luminescence at room temperature. Ion beams can be successfully used also for controllable modification of the nanostructures by introducing defects or changing their phase composition. In the present work, both possibilities are tested by implantation of carbon into thermal SiO 2 films either containing pre-fabricated Si nanocrystals or as-implanted with Si. In the carbon-free SiO 2 films, Si nanocrystals were synthesized at typical Si excess of about 10 at.% and annealing temperatures of 1000 and 1100 °C. It is shown that carbon ion irradiation of the Si-implanted and then annealed SiO 2 films completely quenches a luminescence band at 650-850 nm related to Si nanocrystals and gives rise to emission in the range of 350-650 nm that originated from oxygen-deficient defects. The subsequent final thermal treatment reduces concentration of the matrix defects, but only partially recovers photoluminescence from Si nanocrystals depending on the C dose. The latter is explained by the hindering effect of implanted carbon on growth and crystallization of Si phase inclusions. Strong "white" emission in the spectral range of 350-800 nm is observed only for the equal Si and C concentrations, irrespective of the sequence of carbon introduction and Si nanocrystal formation. This broad spectral band consists of the three sub-bands at around 400, 500 and 620 nm attributed to inclusions of SiC, C and Si phases, respectively. Electron spectroscopy analysis of the annealed layers confirms the presence of silicon carbide phase and carbon precipitates showing the diamond-like sp 3 , not the graphitic sp 2 hybridization. The Si- and C-rich nanoclusters with a size of 3-5 nm were identified in the co-implanted films by electron microscopy as amorphous nanoparticles.

Doping with donor and acceptor impurities is an effective way to control light emission originated from quantum-size effect in Si nanocrystals. Combined measurements of photoluminescence intensity and kinetics give valuable information on mechanisms of the doping influence. Phosphorus, boron, and nitrogen were introduced by ion implantation into Si+-implanted thermal SiO2 films either before or after synthesis of Si nanocrystals performed at Si excess of about 10 at.% and annealing temperatures of 1000 and 1100 °C. After the implantation of the impurity ions the samples were finally annealed at 1000 °C. It is found that, independently of ion kind, the ion irradiation (the first stage of the doping process) completely quenches the photoluminescence related to Si nanocrystals (peak at around 750 nm) and modifies visible luminescence of oxygen-deficient centers in the oxide matrix. The doping with phosphorus increases significantly intensity of the 750 nm photoluminescence excited by a pulse 337 nm laser for the annealing temperature of 1000 °C, while introduction of boron and nitrogen atoms reduces this emission for all the regimes used. In general, the effective lifetimes (ranging from 4 to 40 μs) of the 750 nm photoluminescence correlate with the photoluminescence intensity. Several factors such as radiation damage, influence of impurities on the nanocrystals formation, carrier-impurity interaction are discussed. The photoluminescence decay is dominated by the non-radiative processes due to formation or passivation of dangling bonds, whereas the intensity of photoluminescence (for excitation pulses much shorter than the photoluminescence decay) is mainly determined by the radiative lifetime. The influence of phosphorus doping on radiative recombination in Si quantum dots is analyzed theoretically.

With the aim to establish the possibility of synthesis of GaN inclusions by co-implantation of Ga and N ions in silicon and SiO2 films on a silicon substrate, the chemical composition and photoluminescence of implanted layers have been investigated. It is observed that the heavy loss of implanted atoms occurs owing to the out-diffusion (Ga from Si, and Ga and N from SiO2) in the process of post-implantation annealing. Preliminary implantation of nitrogen to form silicon nitride or oxynitride layers is shown to reduce the degree of impurity losses. In the photoluminescence spectrum of both Si and SiO2 subjected to Ga and N co-implantation, the band at 530-550 nm is present, which can be related to 'defect' luminescence of GaN.