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Неre we report a monolitic long-wavelength vertical cavity surface-emitting laser based on GaAs with bottom GaAs/AlGaAs distributed Bragg reflectors (DBRs), metamorphic optical cavity with In0.41Ga0.59As/In0.25Ga0.75As-active region providing emission near 1.3 μm with high modal optical gain and top dielectric SiO2/Ta2O5 DBRs. We achieve continious wave single-mode operation at room temperature under optical pumping. The proposed approach has potential for high output power and high temperature (up to 200 °C) stable operation.

The article is devoted to the study of light-emitting heterostructures based on GaP(As,N) dilute nitrides, monolithically grown on silicon substrates by plasma-assisted molecular beam epitaxy. Current-voltage characteristics and electroluminescence spectra of the grown heterostructures are obtained. For the first time, a unique effect is observed in GaP(As,N) dilute nitrides - the appearance of white electroluminescence when a reverse bias is applied. The result was obtained due to the original design of the light-emitting heterostructure and the unique properties of dilute nitride solid solutions.

The high-voltage p+–p0–i–n0–n+ structures based on epitaxial gradual GaAs p0–i–n0 junction grown in hydrogen or argon atmosphere have been studied by capacitance-voltage spectroscopy and deep-level transient spectroscopy, DLTS, before and after neutron irradiation. After neutron irradiation, the broad bands associated with electron emission from the states lying above midgap appear in DLTS spectra of both p0–i–n0 GaAs structures. It is assumed that the carrier emission mechanism in the neutron-irradiated GaAs is the same as that in amorphous materials.

The impact of 400 keV Ar+ irradiation on the magnetic and electrical properties of in-plane magnetized magnetic tunnel junction (MTJ) stacks was investigated by ferromagnetic resonance, vibrating sample magnetometry and current-in-plane tunneling techniques. The ion fluences ranged from 10^12 cm−2 to 5 × 10^15 cm−2. Below 10^14 cm−2, the anisotropy of the Ta-capped FeCoB free layer was weakly modulated, following a decrease in the saturation magnetization. The tunnel magnetoresistance (TMR), along with the exchange-bias and the interlayer exchange coupling providing a stable magnetic configuration to the reference layer, decreased continuously. Above 10^14 cm−2, a strong decrease in the saturation magnetization was accompanied by a loss of the magnetic coupling and of the TMR. We show there is an ion-fluence window where the modulation of magnetic anisotropy can occur while preserving a large TMR and stable magnetic configuration of the MTJ, and demonstrate that the layers surrounding the free layer play a decisive role in determining the trend of the magnetic anisotropy modulation resulting from the irradiation. Our results provide guidance for the tailoring of MTJ parameters via ion irradiation, which we propose as a potentially suitable technique for setting the magnetic easy-cone state in MTJ for attaining field-free, fast, and non-stochastic magnetization switching. published

The formation of compositions from polymer layers can significantly increase the monovalent selectivity of ion-conducting materials used in membrane separation processes. It is known that the achieved selectivity strongly correlates with the charge of the upper polymer layer determined through its zeta potential. It is of interest to confirm the strict dependence of the zeta potential on the charge of the upper polymer layer for rough commercial membranes. In this work, we studied the zeta potentials of polyallylamine and sodium polystyrene sulfonate adsorbed on heterogeneous membrane in solutions with different charge numbers of the counterion. It is shown that such coatings are characterized by more negative values of zeta potentials in comparison with those known for smooth coatings and that, upon transition to doubly charged counterions, there is no surface recharge.

A double slot antenna for X-band applications was designed and aerosol jet printing technology was used to fabricate the prototype with silver nano-ink on a flexible polyimide substrate. We investigated the microwave losses of printed antennas in the range from 100 kHz to 27 GHz, obtained at sintering temperatures of 200 °C and 250 °C. Double slot X-band antennas have been calculated and measured. It was found that an operating bandwidth of the printed antenna is 10% in the region of the central frequency of 10.5 GHz. Thus, the possibility of forming antennas on flexible polymer substrates with high functional characteristics by aerosol jet printing method has been demonstrated.

The article presents a comparative analysis of the properties of dough and cookies based on oleogels structured with various substances. Oleogels based on beeswax and its fractions were used as an alternative to solid fat in cookies. We found out that the use of separate beeswax fractions in oleogels makes it possible to obtain dough with different rheological characteristics. It was revealed that there is no regularity in the change in the rheological properties of cookies from the properties of the dough and oleogels. Analysis of the organoleptic profile of the cookie samples showed high values. This fact indicates the acceptability of using oleogels based on individual wax fractions in the biscuits cookies. The results obtained indicate the potential of using oleogels based on beeswax fractions in cookies as an alternative to solid fats.

Fast reserve supply input systems significantly increase the reliability of power supply due to the possibility of preserving the technological process in case of emergency situations. The accuracy of determining the phase of the residual voltage on the busbar in process of connecting the power reserve supply provides a way to significantly reduce the starting overcurrents. In this paper, some modifications of the annealing method for determining the phase of the residual voltage on main section of busbar for emergency mode are considered. The obtained simulation results based on MATLAB environment make it possible to carry out a comparative analysis of a number of calculations for phase estimation design of automatic transfer switch operations based on simulated annealing.

The article is devoted to the development of methods and evaluation of the accuracy of determining the horizontal stiffness of multi-storey buildings basing on the results of instrumental measurements of the self-induced vibrations parameters carried out with the help of high-precision instruments. The proposed studies are extremely relevant in estimating the unsoundness degree of the buildings that have passed a certain period of operation or buildings that have been subjected to severe exposure. The use of dynamic methods of load-bearing structure condition analysis has undeniable advantages, since it excludes the need for a detailed examination, often associated with the necessity to open the enclosing structures and evict the residents of the building. The advantages of using this approach are particularly evident in the survey of a large array of residential buildings that are in heterogeneous operating conditions and require rapid results. The practical application of the methods was tested in the survey of the high-rise apartment buildings of 1-335 series in the city of Irkutsk. However, the need to use dynamic models of small dimension in the evaluation of stiffness parameters makes it inevitable and urgent to solve the problems of assessing the accuracy of such approximations.