Детектирование терагерцевых электромагнитных волн с помощью проводящих антиферромагнетиков

We investigate a mathematical model of a terahertz electromagnetic wave detector based on a conducting antiferromagnet and a heavy metal. The mechanism of resonant straightening of oscillations is based on the inverse spin Hall effect in a heavy metal under spin pumping from an antiferromagnet. It is shown that the frequency dependence of the constant voltage of the detector has a resonant character with a peak corresponding to the frequency of antiferromagnetic resonance. The sensitivity to an alternating terahertz signal of the proposed detector structure is comparable to the sensitivity of modern detectors based on Schottky and Gunn diodes.

Influence of Nonlocality on Transmittance and Reflectance of Hyperbolic Metamaterials

In this paper we investigate transmittance and reflectance spectra of multilayer hyperbolic metamaterials in the presence of strong spatial dispersion. Our analysis revealed a number of intriguing optical phenomena, which cannot be predicted with the local response approximation, such as total reflectance for small angles of incidence or multiple transmittance peaks of resonant character (instead of the respective local counterparts, where almost complete transparency is predicted for small angles of incidence and the broad-angle transparency can be observed within a range of larger angles of incidence). We believe that the observed effects may serve as a working principle in a number of new potential applications, such as spatial filtering, biosensing, or beam steering.

Optical Absorption and Photoluminescence in the Spherical InP/InSb/InP Core/ shell/ shell Nano Structure

The one particle states of charge carriers are considered in InP/InSb/InPcore/shell/shell spherical quantum nano structure at the regime of strong quantization. The results of numerical calculations for the values of the energy of charge carriers for different values of the thickness of the quantizing layer of InSb are presented. The calculations were performed with allowance for the Kaned is persion for electrons and light holes in the InSb layer. The dependence of the number and position of the energy levels of charge carriers in the quantizing layer of InSb on the width of the well (layer thickness) is shown. The dependence of the absorption coefficient and photoluminescence spectra on the energy of incident light of interband transitions have been investigated. The oscillator strengths and selection rules for these transitions have been obtained. The absorption has a strictly resonant character. By the orbital and azimuthal numbers only diagonal inter band transitions are possible. For the radial number, the transitions between the states with the same radial numbers have the highest intensity

Analysis of Broadband Antenna Radiation Pulses

Electromagnetic energy can alter metabolic and biosynthetic processes and under certain parameters of pulsed EMF it can change pulse repetition frequency, operation cycle, power, exposure, as well as it can slow down and inhibit cell growth. MW irradiation range of RNA and DNA – containing virus reduces their infectivity. Inhibition of bacterial cultures growth, changes in phagocytic activity of protein biosynthesis, ultrastructural changes in the cells when exposed to EMF EHF. It was found in experiments with micro-organisms that biological effects of EMF on microorganisms wore a resonant character. One of the basic mechanisms of inhibitory action of EHF radiation on harmful microorganisms is the role of membranes in biological reactions of microorganisms on the EMR.

Nonlinear Electrodynamic Effects of the Torch Discharge Argon Plasma

The measurements of the amplitude-frequency characteristics were done for the high-frequency torch discharge burning in argon. The resonant character of the electric field fourth harmonic attenuation was found. The axial harmonics distribution measurements of the electric field were done for the torch discharge burning in argon-air mixture. The electron concentration in the investigated plasma discharge was evaluated. The selective influence of the change in the electron concentration on the propagation process of the fourth harmonic of the electric field was found.

Features of the Distribution Process of the Electromagnetic Field Frequency Components in the High-Frequency Torch Discharge Plasma

The measurements of axial harmonics distribution of the radial component of the electric field have been made for a torch discharge burning in argon and argon-air mixture. The resonant character of the electric field fourth harmonic attenuation has been found. Using the Saha formula for the two-temperature plasma the electrons concentration and the electrons Langmuir frequency of the investigated plasma discharge have been evaluated.

On Nature of Resonant Transversal Kerr Effect in InMnAs and GaMnAs Layers

Optical and magneto-optical properties of In(Ga)MnAs layers fabricated by laser ablation on GaAs(100) substrates were studied. Spectra of the optical constants and the transversal Kerr effect (TKE) depended substantially on the conditions of layer fabrication and testified to the presence of MnAs inclusions in all the samples. The cross-sectional transmission electron microscopy revealed the presence in the layers of inclusions 10-40 nm in size. At room temperature, a strong resonant band was observed in the TKE spectra of some In(Ga)MnAs layers in the energy range 0.5-2.7 eV. The resonant character of the TKE spectra was explained by excitation of surface plasmons in the MnAs nanoclusters embedded in the semiconductor host.