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Canted antiferromagnets offer great potential in fundamental research and for use in applications due to their unique properties. The presence of the Dzyaloshinskii–Moriya interaction (DMI) leads to the existence of a weak ferromagnetic moment at room temperature. We study both theoretically and experimentally microwave spin pumping by a quasi-ferromagnetic mode from a canted easy plane antiferromagnet with weak ferromagnetism FeBO3. The conversion of a microwave signal into a constant voltage is realized using the inverse spin Hall effect in an iron borate/heavy metal heterostructure. We use an additional bias magnetic field to selectively tune the resonance frequency of such a microwave detector over a wide range up to 43.5 GHz with a potential sensitivity near 2.5 µ V W−1. We confirm the pure spin current nature by changing the polarity of the detected via inverse spin Hall effect voltage by switching the direction of the bias magnetic field. We believe that our results will be useful for the development of highly tunable, portable and sensitive microwave antiferromagnet-based functional devices. [ABSTRACT FROM AUTHOR]

Hybrid magnetic heterostructures made of epitaxial manganite LaSr MnO thin film and an intermetallic superlattice (TeCo/FeCo) were prepared on orthorhombic NdGaO substrates and characterized by means of magneto-optical Kerr effect, magnetoresistance and ferromagnetic resonance. Experimental data show that magnetic interaction between LaSrMnO and (TeCo/FeCo) is of an antiferromagnetic nature. The features observed in magnetotransport characteristics are caused by the magnetization reversal at the interface between manganite thin film and intermetallic superlattice. [ABSTRACT FROM AUTHOR]

Two series of Fe thin films have been electrodeposited onto polycrystalline porous Al substrates using two baths: iron chloride (FeCl) and iron sulfate (FeSO). The texture, strain, and grain size values have been derived from X-ray diffraction experiments. Scanning electron microscopy has been employed for surface morphology. The magnetic properties were inferred from hysteresis curves that were obtained from a vibrating sample magnetometer; the external magnetic field was applied in different directions of the film plane and also perpendicular to the film. Hysteresis curves have been obtained at low temperatures (120 K (−153 °C) to room temperature). We investigate the effects of Al porosity, bath type, and deposition rate on physical properties of these Fe films. A correlation between the structural and magnetic properties is made. Different mechanisms responsible for the coercive field ( H ) behavior have also been investigated. [ABSTRACT FROM AUTHOR]

The effect of substrate temperature, As and P molecular flux densities, and growth rate on the composition of III-PAs solid solution layers prepared by molecular beam epitaxy is experimentally investigated. Experimental data in a wide range of growth conditions are analyzed. The results obtained are presented in the form of a kinetic model for describing the process of formation of the composition in the Group V sublattice of the III-PAs solid solution upon molecular beam epitaxy. The model can be used for choosing the growth conditions of the III-PAs (001) solid-solution layers of a specified composition. [ABSTRACT FROM AUTHOR]

Canted antiferromagnets offer great potential in fundamental research and for use in applications due to their unique properties. The presence of the Dzyaloshinskii–Moriya interaction (DMI) leads to the existence of a weak ferromagnetic moment at room temperature. We study both theoretically and experimentally microwave spin pumping by a quasi-ferromagnetic mode from a canted easy plane antiferromagnet with weak ferromagnetism FeBO3. The conversion of a microwave signal into a constant voltage is realized using the inverse spin Hall effect in an iron borate/heavy metal heterostructure. We use an additional bias magnetic field to selectively tune the resonance frequency of such a microwave detector over a wide range up to 43.5 GHz with a potential sensitivity near 2.5 µ V W−1. We confirm the pure spin current nature by changing the polarity of the detected via inverse spin Hall effect voltage by switching the direction of the bias magnetic field. We believe that our results will be useful for the development of highly tunable, portable and sensitive microwave antiferromagnet-based functional devices. [ABSTRACT FROM AUTHOR]

There is scarce evidence of a relationship between positive and psychosomatic characteristics. This study aimed to examine the associations of somatic burden with psychological resources such as optimism, resilience, and general self-efficacy. Russian participants (n = 1020) completed measures of psychological resources at Time 1 and somatic symptoms at Time 2. The results showed that somatic burden decreased with greater levels of optimism, resilience, and general self-efficacy. Regarding health and sociodemographic characteristics, female sex increased somatic burden in the model with optimism scores, university education decreased somatic burden in the model with resilience scores, and history of COVID-19 disease increased somatic burden in the models with optimism, resilience, and general self-efficacy scores. This study has theoretical and practical contributions. It combines positive psychology and psychosomatic medicine and highlights the value of psychological resource interventions in the treatment and prevention of somatic burden. These findings may be useful for scientists, clinicians, and practitioners.

In this article, we investigate optically induced terahertz radiation in ferromagnetic FeCo layers of varying thickness on Si and SiO 2 substrates. Efforts have been made to account for the influence of the substrate on the parameters of the THz radiation generated by the ferromagnetic FeCo film. The study reveals that the thickness of the ferromagnetic layer and the material of the substrate significantly affect the generation efficiency and spectral characteristics of the THz radiation. Our results also emphasize the importance of accounting for the reflection and transmission coefficients of the THz radiation when analyzing the generation process. The observed radiation features correlate with the magneto-dipole mechanism, triggered by the ultrafast demagnetization of the ferromagnetic material. This research contributes to a better understanding of THz radiation generation mechanisms in ferromagnetic films and may be useful for the further development of THz technology applications in the field of spintronics and other related areas. A key discovery of our study is the identification of a nonmonotonic relationship between the radiation amplitude and pump intensity for thin films on semiconductor substrates. This finding is particularly significant considering that thin films are predominantly used in spintronic emitters due to the characteristic absorption of THz radiation in metals.

Somatic burden has become one of the most common psychological reactions to the COVID-19 pandemic worldwide. This study examined the prevalence of somatic burden, latent profiles, and associated factors of somatic symptoms during the pandemic in a large sample of Russians. We used cross-sectional data from 10,205 Russians collected during October-December, 2021. Prevalence of somatic burden was assessed with the Somatic Symptom Scale-8. Latent profiles of somatic burden were identified using latent profile analysis. Multinomial logistic regression was used to examine demographic, socioeconomic, and psychological associated factors of somatic burden. Over one-third (37%) of the Russians reported being somatised. We selected the three-latent profile solution with high somatic burden profile (16%), medium somatic burden profile (37%), and low somatic burden profile (47%). The associated factors of greater somatic burden were female gender, lower education, history of COVID-19 disease, refusing vaccination against SARS-CoV-2 infection, poorer self-rated health, greater fear of COVID-19 pandemic, and living in regions with higher excess mortality. Overall, this study contributes to knowledge about the prevalence, latent profiles, and associated factors of somatic burden during the COVID-19 pandemic. It can be useful to researchers in psychosomatic medicine and practitioners in the health care system., Competing Interests: NO authors have competing interests., (Copyright: © 2023 Zolotareva et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

We report an increase in terahertz (THz) radiation efficiency due to FeCo/WSe 2 structures in the reflection geometry. This can be attributed to an absorption increase in the alloy FeCo layer at the input FeCo/WSe 2 interface due to constructive interference, as well as to the backward transport of hot carriers from FeCo to WSe 2 . In contrast to the transmission geometry, the THz generation efficiency in the reflection is much less dependent on the magnetic layer thickness. Our results suggest a cheap and efficient way to improve the characteristics of THz spintronic emitters with the conservation of a full set of their important properties.

Polarization of electromagnetic waves plays an extremely important role in interaction of radiation with matter. In particular, interaction of polarized waves with ordered matter strongly depends on orientation and symmetry of vibrations of chemical bonds in crystals. In quantum technologies, the polarization of photons is considered as a "degree of freedom", which is one of the main parameters that ensure efficient quantum computing. However, even for visible light, polarization control is in most cases separated from light emission. In this paper, we report on a new type of polarization control, implemented directly in a spintronic terahertz emitter. The principle of control, realized by a weak magnetic field at room temperature, is based on a spin-reorientation transition (SRT) in an intermetallic heterostructure TbCo 2 /FeCo with uniaxial in-plane magnetic anisotropy. SRT is implemented under magnetic field of variable strength but of a fixed direction, orthogonal to the easy magnetization axis. Variation of the magnetic field strength in the angular (canted) phase of the SRT causes magnetization rotation without changing its magnitude. The charge current excited by the spin-to-charge conversion is orthogonal to the magnetization. As a result, THz polarization rotates synchronously with magnetization when magnetic field strength changes. Importantly, the radiation intensity does not change in this case. Control of polarization by SRT is applicable regardless of the spintronic mechanism of the THz emission, provided that the polarization direction is determined by the magnetic moment orientation. The results obtained open the prospect for the development of the SRT approach for THz emission control.

Intermetallic heterostructures of rare-earth and transition metals exhibit physical properties prospective for various applications. These structures combine giant magnetostriction, controllable magnetic anisotropy, magneto-optical activity and allow spin reorientation transitions (SRT) induced by magnetic field at room temperature. Here, we present the results of a study of spin dynamics induced by ultrafast optical excitation in the [Formula: see text] heterostructure. The time dependence of the light polarization rotation excited by a pump optical pulse with a duration of 35 fs was measured in the total range of the SRT created by external DC magnetic field. We found hysteretic dependence of the polarization rotation on magnetizing field that is specific for spin dynamics near SRT. Enhancement of the rotation is observed in the critical points of the SRT and near the points of magnetization switch from metastable to stable spin states. In the time-domain, two characteristic delays of 20 ps and 200 ps were found, corresponding to the maximum deviation of the light polarization after excitation. The first is explained by the precession motion of spins out of the plane of the structure. The latter is accounted for the spin in-plane deviation from its initial position and thermal relaxation of the anisotropy.

Acoustic resonators based on antiferromagnetic crystals of "easy plane" type, like α -Fe 2 O 3 or FeBO 3 , are of interest for applications in magnetoacoustic sensors of electrical and mechanical values because of high sensitivity of their resonance frequency to variations of external magnetic field or mechanical stress. One of the requirements for magnetic control of resonators is a single-value dependence of resonance frequency on magnetic field strength. This requirement is violated when the geometry of resonator allows for crossover of acoustic modes in the range of magnetic field variation. Designing of resonators with frequency control in a wide range requires knowledge of field-dependent acoustic parameters of the crystals and appropriate method for calculation of the resonator eigenfrequencies. In this letter, we present the complete set of acoustic parameters deduced for α -Fe 2 O 3 single crystal that are used for simulation of acoustic mode structures and spectra of vibrations in disk resonator. The results of simulation using COMSOL Multiphysics software are compared with experimental measurements carried out on two resonators of different ratios of sizes that illustrating continuous and discontinuous dependence of the resonance frequency on the magnetic field. Prevention of discontinuity by correction of the resonator geometry is demonstrated.

The magnetic moment dynamics excited by 35 fs laser pulses in TbCo 2 /FeCo heterostructure is experimentally investigated by pump-probe technique. The studies are carried out in two typical geometries with magnetizing field perpendicular and along to the easy magnetization axis. In the 'easy axis' orientation, high-frequency oscillations of magnetic moments odd with respect to the sign of the magnetizing field are observed using the magneto-optical Kerr effect. In the perpendicular 'hard axis' orientation corresponding to the spin reorientation phase, the experiment shows oscillations that are even with respect to the field. The maximum angle of Kerr rotation as a function of the magnetizing field strength depicts a specific hysteretic loop that reveals ultrafast optical control of uniaxial magnetic anisotropy originally induced during deposition of the heterostructure in a DC magnetic field. The results provide new ways of ultrafast control of magnetic states in exchange coupled intermetallic heterostructures designed for spintronic applications.

Nonlinear parametric coupling of gravity-capillary waves (GCW) by ultrasound wave impinging on a liquid surface is studied experimentally. Modulation of the plane wave radiation pressure by dynamically curved surface of the liquid is considered as a mechanism of the coupling. The standing GCW modes are excited near antinodes by ultrasound beam of carrier frequency 1.030 MHz and coupled parametrically by a plane ultrasound wave with a frequency 1.035 MHz. The beam was modulated at resonance frequencies of GCW overtones f 2 =5.265 Hz and f 4 =7.873 Hz while intensity of the plane wave was modulated at frequency f p =2.657 Hz that corresponds to the nonlinear parametric resonance f p =2f 2 -f 4 . The amplitudes of the parametric interaction of GCW triads are measured and compared with critical condition for GCWs explosive instability., (Copyright © 2019 Elsevier B.V. All rights reserved.)

The authors present data demonstrating effectiveness of activities of Russian health centres. The necessity of modification of their work and patient populations is emphasized with special reference to adaptation ofthe available equipment to the criteria for examination. These proposals are substantiated by the results of studying cardiac rhythm variability and vegetative status in adolescents.