Some results on the miniaturization of silicon-on-insulator (SOI) structures and SOI elements of integrated circuits (IC) were presented. To increase IC performance efficiency, it was necessary to increase barriers and pulling electrical fields by means of high- k dielectrics and nanoscales, which appreciably reduced the mobility of charge carriers at a decrease in the length and width of a channel. Along with an increase in leakage due to source-drain tunnel currents, this limited the physical length of a channel by 10 nm even when silicon was replaced by two-dimensional (2D) materials, such as graphene and metals dihalcogenides. Three-dimensional (3D) integration in the form of double-gate transistors with complete depletion in the SOI structures with high- k buried dielectric (h- k BOX) in the form of so-called fin transistors (FinFET) with two to four gates all around (GAA) and channels from nanowires (NW FET), nanosheets (NS FET), and nanoforks (FS FET), 2D materials, and their 3D packing made it possible to increase the number of transistors on a chip, but not their performance efficiency. The variant considered as an alternative to improve the functionality of these elements was to replace the dielectrics in capacitors and transistors with ferroelectrics and resistors with memristors to turn from binary to neuromorphic logic and, in addition, to implement the principles of radiophotonics and quantum devices and sensors with parallel processing. The dynamically adjustable threshold and polarization of gate ferroelectrics in the complementary MOS metal-oxide-semiconductor field-effect transistors (MOS FET) of heterosystems on a chip (SoC) will retain ultralow power consumption.

The method proposed by Khairulin et al. [JETP Lett. 117, 652 (2023)] for converting the linearly polarized radiation of high-order harmonics of an optical field into the circularly polarized in an optically modulated active medium of a plasma-based x-ray laser has been developed. This method is extended to the case of finite width of spectral lines (finite pulse duration) of high-harmonic radiation and nonlinear interaction of radiation with matter. The transformation of the polarization of the harmonic field is achieved by introducing a phase shift of pi /2 between its polarization components, parallel and orthogonal to the polarization of the modulating field, through resonant dispersion on the spectral wings of the induced gain lines of the active medium and is accompanied by an increase in the power of high harmonics. It is shown that for harmonics with a finite bandwidth, the polarization of the output radiation is nonuniform in time. The reasons for such nonuniformity are analyzed and the conditions for its minimization are found. The influence of nonlinearity and amplified spontaneous emission of the active medium on the high-harmonic polarization is investigated. The possibilities for the experimental implementation of this effect in a neonlike active medium of a plasma x-ray laser based on Ti12+ ions with an unperturbed wavelength of the inverted transition at 32.6 nm are analyzed.

A strong response of nanosystems to the action of weak microwave power through the gap between the sample and the end of the coaxial cable from the microwave generator is detected by measurements at 4.2 K of the conductance of a short-channel p -type silicon transistor and samples with a short quantum point contact in a two-dimensional electron gas of GaAs/AlGaAs heterostructures. The conductance response is gigantic in the tunnel mode of the devices, and the sign of the microwave photoconductance outside this mode depended on the mesoscopic state of the sample and the studied range of gate voltage. The nature of the discovered effects is elucidated by modeling mesoscopic transport within the framework of single-particle quantum mechanics and the Landauer formula as well as by analyzing the basic circuits of electrical control of the semiconductor device. The main reason for the response of nanosystems to microwave exposure is forced in-phase charge oscillations in contacts to the semiconductor due to capacitive coupling in the near metallic environment of the sample.

We study microwave photoresponse of a short p-channel MOSFET in the subthreshold regime at temperatures from room to helium. We observe large (several times) enhancement of the MOSFET conductance at 300 K, an order at 77 K, and giant (up to 4–5 orders of magnitude) at 4.2 K. It is shown that this giant enhancement is mainly due to microwave-induced hole tunneling between the MOSFET source and drain. The result obtained exhibits real possibility of developing substantially different kind of microwave radiation detectors fabricated on the basis of ordinary MOS-technology.

Quantum point contacts with a short (100-nm) channel in a high-mobility two-dimensional electron gas of GaAs/Al(Ga)As heterostructures and a short-channel p-type field-effect transistor in a silicon-on-insulator structure were fabricated and studied experimentally and by modeling at the Rzhanov Institute of Semiconductor Physics, Siberian Branch, Russian Academy of Sciences, Novosibirsk, Russia, in order to study the response of the samples to weak irradiation by an electromagnetic field with a frequency of 2 GHz. This response in the tunneling mode at a temperature of 4.2 K turned out to be giant and was observed against the background of features caused by impurity disorder.

The spectral characteristics of the optically detected magnetic resonance of negatively charged nitrogen–vacancy (NV ^- ) centers in synthetic diamonds and nanopillars on their surface formed by a focused Ga ^+ ion beam, when the lower spin sublevels are populated with microwave radiation, are studied. In the course of studies for emerging spin resonances at different values of the external magnetic field, both a significant decrease in the gyromagnetic ratio and a significant drop in the photoluminescence contrast are revealed for the directions of the NV ^- centers inclined to the axis of the nanopillars due to residual defects from ion etching recorded on Raman spectra in the form of peaks from amorphous carbon and graphite and the stresses they create.

Magnetotransport measurements have been carried out for pristine and irradiated Y Ba2Cu3O7−x films. The measurements reveal a crossover from the clean superconducting limit to the dirty one with an increase in the impurity scattering rate Γ produced by a certain dose of irradiation. For the clean limit, the critical temperature Tc0 decreases with Γ, while the initial slope K=|dHc2/dT|Tc0 increases. We find a nice agreement between these experimental data and a model of d-wave superconductors with anisotropic impurity scattering. Such dose-dependencies of Tc0 and K reveal the superconducting coherence length ξ0 to be quasi-invariant in the clean limit. For the dirty limit, ξ0 increases with Γ due to a decrease in both the quantities Tc0 and K. Though, this decrease appears slower than predicted by the textbook picture of d-wave superconductors. Such discrepancy can be produced by an irradiation-induced modulated disorder responsible for the formation of (d+s)-wave pairing.

The method proposed in [I.R. Khairulin et al., JETP Letters 117(9), 652 (2023)] for converting the linearly polarized radiation of high-order harmonics of an optical field into the circularly polarized in an optically modulated active medium of a plasma-based X-ray laser has been de-veloped. This method is extended to the case of finite width of spectral lines (finite pulse dura-tion) of high harmonic radiation and nonlinear interaction of radiation with matter. The trans-formation of the polarization of the harmonic field is achieved by introducing a phase shift of π/2 between its polarization components, parallel and orthogonal to the polarization of the modulating field, through resonant dispersion on the spectral wings of the induced gain lines of the active medium and is accompanied by an increase in the power of high harmonics. It is shown that for harmonics with a finite bandwidth, the polarization of the output radiation is non-uniform in time. The reasons for such non-uniformity are analyzed and the conditions for its minimization are found. The influence of nonlinearity and amplified spontaneous radiation of the active medium on the high-harmonic polarization is investigated. The possibilities for the experimental implementation of this effect in a neon-like active medium of a plasma X-ray laser based on Ti12+ ions with an unperturbed wavelength of the inverted transition at 32.6 nm are analyzed.

The silicon-on-sapphire (SOS) pseudo-MOSFETs with high -k buried hafnium dioxide interlayer (IL) were investigated after the hydrogen induced Si and HfO2 layer transfer on c-sapphire wafers and annealing at 600-1100 degrees C. HRTEM, GIXRD and Raman measurements were used to reveal the hafnia phases for furnace and rapid thermal annealings (FA and RTA).

The results are presented on changes in the parameters of pseudo-MOS transistors based on silicon-on-sapphire (SOS) mesastructures upon irradiation with swift heavy ions (SHIs) of Xe ^+26 (150 MeV) and Bi ^+51 (670 MeV) to a fluence of 2 × 10^11 cm ^-2 , indicating the accumulation of mechanical stresses and charges in the intermediate ferroelectric (Fe) layers of HfO _2 films (HO) with a thickness of 20 nm and Hf _0.5 Zr _0.5 O _2 (HZO) laminated with inserts of Al _2 O _3 monolayers (HA, HZA) or without them. SOS heterostructures are formed by direct bonding and hydrogen transfer of a silicon film (500 nm) with HA and HZA nanolayers pre-applied by plasma-stimulated atomic layer deposition onto sapphire. Electrophysical parameters are determined from the drain current—gate voltage characteristics ( I_ds – V_g) of pseudo-MOS transistors with tungsten drain/source electrodes (100 nm) deposited by magnetron sputtering on SOS mesastructures through a lithographic mask. Comparison of the characteristics with Raman scattering analysis showed the correspondence of the mechanical compressive stresses introduced by SHI irradiation in silicon with the ratios of the Xe and Bi track volumes in the HA ferroelectric and sapphire.

We report on the implementation of a terahertz two-photon quantum cascade laser operating in a continuous wave mode. Lasers that can emit two photons as a result of the relaxation of a single electron between two states of the same parity have been discussed since the early days of the laser era, but implementation has been hampered by the lack of a suitable gain medium. The semiconductor structure of a quantum cascade laser seems to be an ideal medium for realizing such two-photon emission. Our work demonstrates dual-band laser radiation in the range of 3.1-3.9 THz (104-130 cm(-1)) at temperatures up to 90 K.

Amplified interband emission within the 14–24 μm range is investigated in HgCdTe-based quantum wells under optical pumping. Carrier lifetimes are shown to be marginally limited only by Shockley–Read–Hall recombination, fully realizing the advantage of relativistic energy spectra of 2D HgCdTe in terms of suppressing the Auger processes. By carefully optimizing the waveguides and mitigating carrier heating, we achieve amplification thresholds as low as 1.5–2 W/cm2 at a pulse duration of 20–500 μs. With last generation quantum cascade lasers used for optical pumping, we estimate that continuous-wave HgCdTe lasers can operate in the very long-wavelength range (15–30 μm) and beyond.

Silicon-on-sapphire (SOS) substrates with nanolayers of silicon and hafnium dioxide are studied structurally, electrophysically, and optically depending on the thickness of the substrate. It is shown that the biaxial tensile stress in the HfO2 intermediate layer induced as a result of heat treatment of such structures stimulates the current hysteresis in the channel of the SOS pseudoMOS transistor due to the large difference in the coefficients of thermal expansion between the silicon layer, sapphire layer, and hafnium dioxide layer. It is found that a decrease in mechanical stress in hafnium dioxide leads to an increase in the coercive field and ferroelectric switching at low fields in hafnium dioxide nanolayers.

The optimal regime of three-photon resonant excitation of a helium atom via a femtosecond ultraviolet (UV) pulse was discovered and numerically studied, at which the maximum power of the third harmonic of the UV field is achieved in the spectrum of dipole acceleration (the second time derivative of the induced dipole moment) of the atom. It is shown that the optimal frequency of the UV field nearly coincides with the frequency of the three-photon transition |1s2⟩–|1s2p⟩, taking into account its shift as a result of the dynamic Stark effect, and the intensity of the UV field is dictated by the condition of maximizing the product of the populations of the |1s2⟩ and |1s2p⟩ states, averaged over the time interval during which the UV field is non-zero. For the considered UV field durations, from 10 to 100 cycles of the carrier frequency (from units to tens of femtoseconds), the optimal intensity lies in the range from 1014 W/cm2 to several units of 1014 W/cm2. It is shown that with an optimal choice of the frequency and intensity of the UV field, the dynamics of excitation of bound and continuum states, as well as the shape of the time envelope of the dipole acceleration of the atom, weakly depend on the duration of the UV field envelope; only their time scale changes significantly. In addition, under optimal conditions, the average power of the third harmonic signal in the dipole acceleration spectrum is practically independent of the duration of the UV field envelope.

A method is proposed for converting linearly polarized radiation of a single harmonic or a combination of high-order harmonics of an optical field, which form a train of subfemto-/attosecond pulses, into elliptically and, in particular, circularly polarized radiation in an optically modulated neon-like active medium of an X‑ray plasma laser. It is shown that this method can provide a high energy efficiency of radiation conversion due to the amplification of the harmonic field, and is also insensitive to changes in the number of high harmonics that form the amplified pulses. The possibility of experimental implementation of the method is considered on the example of an active plasma of neon-like Ti12+ ions with an unperturbed inverted transition wavelength of 32.6 nm.

In Khairulin et al. [Sci. Rep. 12, 6204 (2022)] we proposed a method for amplifying a train of sub-femtosecond pulses of circularly or elliptically polarized extreme ultraviolet radiation, composed by high-order harmonics of an infrared (IR) laser field, in a neonlike active medium of a plasma-based x-ray laser, additionally irradiated with a replica of a fundamental frequency laser field used to generate harmonics. Here we present the analytical theory and numerical study of an amplification process of an individual harmonic with either preservation of its polarization state or ellipticity enhancement. We also analyze in detail the spectral-temporal and polarization properties of a sub-femtosecond pulse train formed by a set of elliptically or circularly polarized harmonics during the propagation through the medium. We discuss also the possibility of an experimental implementation of the suggested technique in an active medium of an x-ray laser based on neonlike Ti12+ ions irradiated by an IR laser field with a wavelength of 3.2 & mu;m.

Magnetotransport measurements were carried out for YBa 2 Cu 3 O 7-x (YBCO) thin films in external perpendicular magnetic fields of H. The studies were performed both for the virgin samples and for the irradiated ones. Xenon ions were used as an external irradiation. Thus we studied features of the broadening of superconducting transition in YBCO films (virgin and irradiated). The broadening of superconducting drop was analyzed depending on an external magnetic field H, as well as on an irradiation dose n D . When processing the experimental data R(H,T), we studied a criterion for determination of temperature dependence of the upper critical field H c2 (T). The criterion was analyzed depending on the defect concentration in the film corresponding to a certain value of n D . It was found out that for a virgin sample, H c2 should be determined by the resistance level R=0.4R N inside the superconducting transition, where R N =R(T=100 K). With a gradual increase in n D , this resistance level decreases. At sufficiently high radiation doses n D >7·10 12 cm -2 , the H c2 (T) phase transition line should be determined by the level R~0. Keywords: thin films, HTSC, xenon ion irradiation, magnetotransport studies, broadening of the superconducting transition, upper critical field, phase transition line, Tinkham's formula, Abrikosov vortices.

Исследованы спектральные характеристики оптически детектируемого магнитного резонанса отрицательно заряженных центров азот-вакансия (NV-) в синтетических алмазах и наностолбах на их поверхности, сформированных сфокусированным ионным пучком Ga+ при заселении нижних спиновых подуровней микроволновым излучением. В ходе исследований для проявляющихся спиновых резонансов при различных значениях внешнего магнитного поля выявлено как существенное уменьшение гиромагнитного соотношения, так и существенное падение контраста фотолюминесценции для направлений центров NV-, наклонных к оси наностолбов вследствие остаточных дефектов от ионного травления, регистрируемых на спектрах комбинационного рассеяния света в форме пиков от аморфного углерода и графита и создаваемых ими напряжений. The spectral characteristics of optically detectable magnetic resonance (ODMR) are investigated for negatively charged nitrogen-vacancy (NV-) centers in synthetic diamonds and nanopillars on their surface formed by a Ga+ focused ion beam (FIB), when lower spin sublevels are populated with the microwave radiation in 0-20 G magnetic fields. Both a significant decrease in the gyromagnetic ratio and the quenching of luminescence from the NV- centers inclined to the nanopillar axis are revealed due to residual defects and stresses created by them.

In this paper, the method of transforming the Mössbauer gamma radiation into a train of ultrashort pulses in a resonant nuclear absorber, which harmonically oscillates as a whole along the direction of radiation propagation [1], was generalized to the case of multifrequency absorber oscillations. Based on the example of the Mössbauer absorber 57 Fe and the radioactive Mössbauer source of 14.4 keV photons 57 Co, it is shown that under optimal conditions, adding new harmonics of the fundamental frequency to the law of absorber motion makes it possible to reduce the duration and increase the intensity of the generated pulses while maintaining their repetition period. An optimal law of absorber motion leading to the formation of the shortest and most intense pulses is derived. It corresponds to periodic fast displacements of the absorber relative to the source by the wavelength of resonant radiation. In this case, the duration of each individual pulse of the output radiation is determined by the duration of the constructive interference that appears and disappears with a rapid change in the relative phase between the incident field and the field coherently forward-scattered by the nuclei of the moving absorber due to the Doppler effect. The possibility of transforming quasi-monochromatic radiation into a single intense short pulse, the duration and instant of the formation of which are determined by the duration and instant of the onset of the absorber displacement, is shown.