Дважды отрицательные среды на основе антиферромагнитных полупроводников для терагерцевого диапазона частот

The paper presents the results of a theoretical study of the dispersion characteristics of electromagnetic waves (EMW) existing in a transversely magnetized antiferromagnetic (AFM) semiconductor with loss. An AFM semiconductor is an infinite bi-gyrotropic medium, the effective material parameters of which are twice negative in several frequency ranges. It was found that these frequency regions are in the terahertz range and there are four backward EMEs in them, two of which are TE waves, and the other two are TM waves.

COMPARISON OF DISPERSION CHARACTERISTICS OF SOLID-CORE PCFs INFILTRATED WITH PROPANOL AND ETHANOL

In this paper, we propose the solid-core photonic crystal fibers (PCFs) with hexagonal cladding infiltrated with propanol in the air-holes. The dispersion characteristics and zero- dispersion wavelengths of these PCFs have been compared with previous publications and analyzed in detail. By investigating the dependence of the dispersion characteristics on the air-hole diameters, we determine the optimal structures with 1 µm of that. The PCF infiltrated with propanol exhibits flatter and smaller dispersion characteristic and the zero-dispersion wavelength shifted towards a longer wavelength, 24 nm compared with ethanol permeable PCFs [17]. This result shows that structure with a diameter of air-holes by 1µm is suitable for supercontinuum (SC) generation in the near- infrared wavelength range.

Plasmon resonance at the interface dielectric - nanocomposite material with superconducting inclusions

This article theoretically considers surface plasmon resonance in composite structures. The features of the surface plasmon resonance arising at the interface with media containing nanoparticles from a high-temperature superconductor are investigated. The dielectric constant of spherical superconducting inclusions is considered taking into account Gorter-Casimir two-fluid model. The temperature dependence of the electrodynamic parameters of the superconductor is taken into account. The two-fluid model, the dependence of the concentration of non-superconducting electrons in a superconductor is often used as the fourth power of temperature nn~T4. In this work, a phenomenological model is used, according to which the electron concentration of non-superconducting electrons in a superconductor is determined by the formula nn~Tγ with γ=1.3÷2. This model is in good agreement with experimental data for high-temperature ceramic superconductors. The dispersion characteristics of surface plasmons arising in a planar structure with a thin nanocomposite superconductor layer are investigated. It is shown that the dispersion characteristics depend significantly on temperature.