Relatively recently, it became known that the interaction of photons with free electrons leads to quantum entanglement of photons. Such photons can be used in many applications of quantum technologies. Typically, to study quantum entanglement, photons are assumed to be monochromatic, although in reality they are not. This paper shows that if non-monochromatic photons are taken into account, their quantum entanglement, based on von Neumann entropy, can differ significantly from the case of monochromatic photons. It has been shown that the entanglement of non-monochromatic photons can be large and reach the maximum possible value. (c) 2024 Optica Publishing Group. All rights, including for text and data mining (TDM), Artificial Intelligence (AI) training, and similar technologies, are reserved.

The analysis of the characteristics of activated carbon obtained by thermochemical activation of hydrolytic lignin with sodium hydroxide is presented. The design of the measuring cell of the supercapacitor is described, as well as a method for measuring the capacitance and internal resistance of the supercapacitor. The specific capacitance of the electrode based on the activated carbon under study, as well as the internal resistance of the cell of a supercapacitor with neutral aqueous electrolytes of 1 M sodium sulfate and 4 M sodium chloride, were determined.

A study on the dependence of the thermal conductivity of the percolation network of carbon nanotubes (or CNTs) on the type and degree of functionalization has been carried out. The study was focused on the influence of the more commonly used -COOH, -OH and -СОNH2 groups. A non-linear dependence of the conductivity on the number of functional groups has been revealed. A small number of functional groups can improve conductivity, and a large one can impair it. We presuppose the existence of competing processes that increase thermal conductivity (changes in the CNT geometry, improvement of the contact between them) and enhance photon scattering (emergence of defects and scattering centers). The data can be used for controlling the thermophysical properties of the CNTs as well as determining the optimal degree of functionalization during the development of composites and nanodevices.

A method is proposed for increasing the resistance of a superhydrophobic coating based on a CNT xerogel to frost deposition through the use of decorating nanoparticles. The effects of the addition of fullerenes, carbon nanoonions (CNOs), detonation nanodiamonds, silicon dioxide, and paraffin to the xerogel are tested. An increase in the resistance of the coating to the deposition of condensate in the form of frost is revealed. The addition of fullerene C 60 leads to the best results. Increasing the resistance to icing allows us to spend less power on heating the surface during short cold snaps, bypassing the anti-icing properties of the protective superhydrophobic layer. However, the application of this approach shows a deterioration in the resistance of the coating to the penetration of the spray. This is given a qualitative explanation and measures to combat it are proposed. No effect of the additives on the mechanical properties of the coating or its resistance to damage is detected. In additon, decorating additives affect the formation of the coating relief. With this, it is possible to influence the stochastic processes of the formation of roughness during the drying of the xerogel.

The previous article introduced the idea of a superhydrophobic coating from carbon nanoparticles that can combine the lotus effect, the slip effect and electric current heating. A further development of this idea was suggested. The article demonstrated the possibility of a practical implementation of the suggested approach using two coating layers—the electro-thermal layer from carbon nanotubes and the water-repellent layer from onion-like carbons. This coating allows to conserve energy during periods of slight cooling simply due to the use of the lotus effect. The heating is used to prevent icing at lower temperatures. The best contact angle achieved equals 155.9 ± 0.5 degrees at a slip start angle of 1.2 ± 0.5 degrees.

Usually in quantum optics, the theory of large- and small-scale waveguide beam splitters is the same. In this paper, it is shown that the theory of the nanoscale waveguide beamsplitter has a significant difference from a similar device, but of a larger scale. It is shown that the previously known theory of the waveguide beam splitter is a particular case of the theory presented here. The wave function at the output ports of the nanoscale beam splitter is analyzed. The results obtained are sensitive to the size of the beam splitter, the coupling parameter of the two waveguides, and the degree of nonmonochromaticity of the photons entering the first and second ports of the beam splitter. The results are important for quantum technologies using a nanosized beam splitter.

It is well known that a beam splitter (BS) can be used as a source of photon quantum entanglement. This is due to the fact that the statistics of photons changes at the output ports of the BS. Usually, quantum entanglement and photon statistics take into account the constancy of the reflection coefficient R or the transmission coefficient T of the BS, where R+T=1. It has recently been shown that if BS is used in the form of coupled waveguides, the coefficients R and T will depend on the photon frequencies. In this paper, it is shown that the quantum entanglement and statistics of photons at the output ports of a BS can change significantly if a BS is used in the form of coupled waveguides, where the coefficients R and T are frequency-dependent.

A simple method for applying superhydrophobic coatings based on carbon nano-onions obtained by a low-cost and technological synthesis method is proposed. The dependence of the hydrophobic properties of the coating on the application conditions, surface roughness and parameters of nanoobjects is analyzed.

The possibility of creating an anti-icing self-heating coating based on carbon nanotubes was explored. The influence of the quantity of coating layers on its conductive properties was studied. The possibility of modification of conductivity through annealing has been explored. Dependences of conductivity on the duration of the process of annealing are shown. An explanation to these dependences is given. A comparative analysis of the dependences for different types of CNTs has been conducted.

For the first time a superhydrophobic coating based on carbon nano-onions (multilayer fullerenes) synthesized through a cheap and technological method was obtained. Two simple and easily reproducible techniques of application were suggested. An opportunity of using the coating to control the composition and humidity of air was explored. Anti-icing properties were researched.

For the first time, a superhydrophobic coating based on onion-like carbon was synthesized by an economically feasible and scalable method was obtained. Two simple and easily reproducible methods of application are proposed. The possibility of using such coating to detect the composition and humidity of the air as well as its anti-icing properties are studied.

PAS spectroscopy is nowadays well recognized as a powerful tool of microstructure investigations of condensed matter. As a result of the experiments, data were obtained show the effect of cavitation on the occurrence of surface defects in a titanium alloy on various time characteristics.

Carbon nanotubes are a promising material for nanoelectronics and conducting composites. The conductivity and the width of the forbidden region of CNTs is determined mainly by their chirality. The possibility of modification of these parameters through applying functional groups has been explored. Dependences of conductivity on the degree of functionalization and the type of functional groups are shown. An explanation to these dependences is given. A comparative analysis of the dependences for different types of CNTs has been conducted.

A method of obtaining coatings with a high degree of hydrophobicity out of carbon nanoobjects is suggested. The method of application of the coating is technological, available for application to nearly all types of surfaces and does not require special conditions. Main factors that influence the properties of the given coating are pointed out. Main factors that influence the properties of the given coating are pointed out. Electrophysical properties of the coating are measured, an approach to creating a coating with electrical heating is suggested.

The effect of the processes of cavitational and electrocorrosive destruction of metal on the TL-5 titanium alloy is studied in the work. The fact of deceleration of destruction of the alloy while affected by destructive factors is shown. The reasons for this effect are listed. Illustrations of the main stages of destruction obtained through scanning electron microscopy are provided. In order to achieve the cavitational effect an ultrasonic disperser was used.

The creation of hydrophobic, antifreeze and self-cleaning coatings is currently being pursued by many industrial sectors. The potential applications include the production of liquid and gas separators and filters, new materials, optical and microelectronic devices, and textiles and clothing. These coatings will also have wide application in the construction and automobile industries, shipping, and energy and agricultural sectors. The article proposes a simple approach to the creation of superhydrophobic and antifreeze coatings, by applying powder from multi-walled carbon nanotubes (MW-CNTs) to the sample surface. This method enables combination of the necessary factors: low surface energy, micro–nano-roughness and hierarchical multi-scale. The authors investigated the dependence of the wetting angle of such a surface on the time, type and degree of functionalization. The electrophysical properties of modified MW-CNTs were studied over wide frequency and temperature ranges. This method of obtaining hydrophobic coatings differs from currently available methods in that it is simpler to prepare, is of lower cost and has less environmental impact. The proposed approach can be used to create superhydrophobic coatings that have the additional function of removing static charge and therefore reducing surface heating, and which can be used in the field of energetics for protection against the freezing of wind turbine blades and aircraft surfaces.

1 Northern Arctic Federal University named after M.V. Lomonosov, Severnaya Dvina Emb. 17, 163002, 5 Arkhangelsk, Russia 6 * Correspondence: m.eseev@narfu.ru, agoshev@hotmail.com; Tel.: +7–902–190–5195 7 8 9 Abstract: The creation of hydrophobic, antifreeze and self-cleaning coatings is currently being 10 pursued by many industrial sectors. The potential applications include the production of liquid and 11 gas separators and filters, new materials, optical and microelectronic devices, and textiles and 12 clothing. These coatings will also have wide application in the construction and automobile 13 industries, shipping, and energy and agricultural sectors. 14 The article proposes a simple approach to the creation of superhydrophobic and antifreeze 15 coatings, by applying powder from multi-walled carbon nanotubes (MW-CNTs) to the sample 16 surface. This method enables combination of the necessary factors: low surface energy, micro– 17 nano-roughness and hierarchical multi-scale. The authors investigated the dependence of the 18 wetting angle of such a surface on the time, type and degree of functionalization. The electrophysical 19 properties of modified MW-CNTs were studied over wide frequency and temperature ranges. This 20 method of obtaining hydrophobic coatings differs from currently available methods in that it is 21 simpler to prepare, is of lower cost and has less environmental impact. The proposed approach can 22 be used to create superhydrophobic coatings that have the additional function of removing static 23 charge and therefore reducing surface heating, and which can be used in the field of energetics for 24 protection against the freezing of wind turbine blades and aircraft surfaces. 25