The development of a two-photon source based on the effect of spontaneous four-wave mixing (SFWM) of light involves solving a number of tasks: from choosing a structure of suitable length and nonlinearity to a detailed analysis of dispersion properties. We consider an integrated spiral waveguide made of a composite polymer using optical lithography as a potential photon pair generation scheme. As a result of the analysis of the modes and dispersion properties, it was possible to determine the zero-dispersion wavelengths necessary for the occurrence of the SFWM effect, as well as the main limitations of the wavelength range of the generated two-photon fields.

We have developed the theory which describes the magnetization curves of an ensemble of single-domain particles. This theory takes into account their thermal excitations, and it is essentially a generalization of the two-level Stoner–Wohlfarth model and its relaxation variant, as well as a multilevel relaxation model for describing Mössbauer spectra. A fundamentally new feature of our theory is the solution of a system of differential equations for nonequilibrium populations of stochastic states. The resulting model includes the physical mechanisms underlying the formation of nanoparticle magnetization curves in real-world situations and self-consistently describes the qualitative features of the transformation of these curves depending on temperature, direction, and external field strength.

The properties of Cu/NC/D/Ni memristive structures with thin layers of (CoFe)x(SiO2)100–x nanocomposite (230 nm) and LiNbO3 dielectric (14–28 nm) are studied. It is shown that annealing the structures at 300°C for 10 min leads to increase in the ratio of the high-resistance state (Roff) to the low-resistance state (Ron). Heat treatment also increases the stability of resistive state. The increase of the LiNbO3 layer thickness increases in the values of Roff, Ron, and the resistive switching (RS) voltage of the structures to the low-resistance state. The structures exhibit stable multilevel RS in successive cycles of potentiation and depression, which, coupled with plasticity and a high Roff/Ron ratio, demonstrates the prospects of their use as synapses in the development of neuromorphic systems.

This paper investigates the possibility of using thin-film coatings based on molybdenum-silicon (Mo–Si) alloy as opaque masking layers for a new generation of photomasks (opaque Mo–Si on glass, OMOG) intended for nanometer-range 193 nm wavelength lithography technologies. The relevance of this work is due to the limitations of classic binary photomasks (BIM) of the “chromium on glass” (COG) type, which does not allow the required resolution to be achieved due to the need to form thick chromium layers to achieve optimal optical density. The work investigates the dependence of the optical density of Mo–Si films on their composition and thickness. To this end, a series of samples were formed on different types of substrates and measurements of optical, structural, and elemental parameters were carried out using spectrophotometry, atomic force microscopy, and energy dispersive analysis. It is shown that the use of Mo–Si films allow the required optical density to be achieved with a smaller layer thickness compared to traditional chrome coatings, which contributes to improving the etching process when forming a topological pattern on a photomask (PM). The results confirm the promise of using Mo–Si films as a masking material for photomasks with a design standard of 32–28 nm.

MEMS switches are promising for mobile radar systems and electromagnetic warfare, but their performance has not yet reached the required level. Miniature electrostatic actuators produce weak contact force, preventing low contact resistance. In turn, low opening force leads to contact stiction. This paper presents a MEMS switch based on a microactuator with increased contact and opening forces. The design methodology, contact resistance, and microwave characteristics of the switch are described.

A theoretical model for the propagation of surface plasma oscillations along a metallic nanolayer is constructed within the quantum theory of transport phenomena. The conductor constant energy surface is assumed to be an ellipsoid of revolution. Charge carriers surface scattering is taken into account by using Soffer boundary conditions. Analytical expressions are derived for the longitudinal and transverse surface wave characteristics: the propagation coefficient, the longitudinal and transverse attenuation coefficients, and the propagation length. An analysis of the dependences of the surface wave longitudinal characteristics on dimensionless parameters: the metallic nanolayer thickness, the surface wave frequency, the insulating layers permittivity, the roughness parameters of the metal–dielectric interface, and the ellipticity parameter of the isoenergetic surface is performed.

When creating precise temperature control systems, it is necessary to consider numerous factors affecting the functional and operational characteristics of thermoelectric systems. In this study, the metrological support for studying and monitoring the parameters of thermoelectric materials, structures, and devices at all stages of the development and production of thermoelectric systems is considered. The developed and obtained effective nanostructured materials on the basis of BiTeSe and BiSbTe with a dimensionless thermoelectric figure of merit of 1.16 and 1.24, respectively, are presented. Complex studies of these materials are carried out, the mechanisms of electrical and thermal conductivity are determined, and the relationship between their structure and parameters is established. The technology of metal-dielectric commutation matrices based on oxidized aluminum alloys for thermoelectric modules is developed. The kinetics of the growth of porous anodic oxide films on aluminum alloys is determined. The methods of forming and using contact materials in thermoelectric modules, whose specific contact resistance is 10–9 Ω m2 and adhesion strength is up to 19 MPa are substantiated. A technology for sealing thermoelectric modules with increased reliability and mechanical strength is developed. The design criteria are defined and substantiatied, based on which the power supplies for thermoelectric systems, having a low pulsation level (0.3%) and high degree of efficiency (93%), are manufactured. To calculate the temperature in electronic thermometers mathematical models allowing the temperature determination with an accuracy of 5 × 10–3 K are developed and justified. The presented precise electronic temperature measuring instruments, as well as precise thermoelectric thermostats, calibrators, and heat and cold chambers, have operating temperatures ranging from –50 to +60°C.

When solving polarimetry problems where optical beam-splitting schemes are not feasible for reconstructing individual parameters on individual measuring devices, metasurfaces with reduced symmetry are often used. This is a technologically challenging approach due to the high precision requirements of lithography. In this paper, we propose an alternative concept and device implementation in which the required symmetry-free operation is achieved by patterning four contacts adjacent to a two-dimensional semiconductor crystal. Illumination of such a device generates a set of signals from which, with preliminary calibration, it is possible to reconstruct the full polarization state of the incident radiation. The influence of contact shape on polarization sensitivity and phase delay arises from the polarization-sensitive enhancement of the electric field near the metal edges, which is independent of the photovoltage generation mechanism in the two-dimensional crystal, making this concept applicable to a wide range of materials.

Thin-film materials used as functional layers in ferroelectric random-access memory (FeRAM) devices are polycrystalline, which potentially allows to set intermediate quasi-independent polarization states. Ferroelectric Hf0.5Zr0.5O2 (HZO) is of particular interest and a leading candidate owing to its excellent CMOS compatibility. Here, we describe the methodology to implement multilevel polarization switching in TiN/HZO/TiN metal-ferroelectric-metal (MFM) capacitors as a compact alternative to FeRAM cell scaling and as a model system for further ferroelectric field-effect transistor (FeFET) implementation. Using binary search, we find the voltage amplitudes to write the required intermediate polarization values, and then stabilize them using a closed-loop software verification scheme that adjusts the write amplitude to maintain a reference polarization. Following this approach, we reproducibly set and read 8 well-separated intermediate states (2Pr = 4–28 μC/cm2). When operating in a closed-loop, we observe a slight softening of the intermediate states, while the most saturated state remains relatively stable on the timescale of the measurements; a qualitative explanation can be obtained assuming the energy distribution of charged defects in HZO band gap at the interface. Good retention is found over several hours at both room temperature and 70°C. Only small, level-dependent transients (maximum around 1 s) are observed in case of rewriting the state which subsequently relaxes and does not cause the mixing of the states. The concept of multibit operation in HZO capacitors is discussed based on the obtained results.

Switches fabricated using microelectromechanical systems (MEMS) technology are considered as a new element base for microwave devices. Small size, high isolation, low insertion loss and power consumption make them attractive for wireless communication and radar systems. However, the implementation of MEMS switches in microwave technology is hampered by their poor reliability. Switches often fail due to contact resistance growth. The contacts degrade due to material transfer under high switching current. In this paper, the simulation results for resistive heating of microcontacts using the finite element method are presented.