E. G. Chizhevskii

Terahertz injection lasers based on PbSnSe alloy with an emission wavelength up to 46.5 μm

Diffusion injection lasers based on Pb1 – xSnxSe alloy, emitting in a wide spectral range of 10–46.5 μm depending on the composition and temperatures are fabricated. A technology for growing high-quality single crystals from the vapor phase under conditions of free growth is developed. The dependences of the total emission intensity on the pump current and the emission spectra of injection lasers based on Pb1 – xSnxSe are studied. In these samples, lasing of long-wavelength radiation to a record wavelength of 46.5 μm is achieved.

Magnetotransport in thin epitaxial Bi2Se3 films

The magnetoconductivity of thin Bi2Se3 films covered by a protective Se layer and grown at (111) BaF2 substrates is studied. It is shown that the negative magnetoconductivity observed at low magnetic fields and caused by the effect of weak antilocalization, as well as the Shubnikov−de Haas oscillations at higher fields, is determined only by the magnetic field component perpendicular to the film plane. The obtained experimental results can be reasonably interpreted under the assumption that the studied films exhibit two-dimensional topologically protected electron states. Moreover, the contribution of these states to the total conductivity turns out to be the dominant one.

Dispersion of the refractive index of epitaxial Pb1 − xEuxTe (0 ≤ x ≤ 1) alloy layers below the absorption edge

The transmittance spectra of epitaxial Pb1 − xEuxTe (0 ≤x ≤ 0.1) alloy layers are exploited to study the dispersion of their refractive index in the spectral range from 650 to 8000 cm−1 (below the absorption edge). The refractive index and the position of the absorption edge as functions of the composition parameter of the alloys are determined at two temperatures, 80 and 295 K. The refractive index is calculated in the context of the classic wave concepts of propagation of electromagnetic radiation. The experimentally determined dispersion dependences are described by the empiric Sellmeier expression of the second order. From analysis of the transmittance of the layers, it follows that the band gap of the epitaxial Pb1 − xEuxTe alloys increases with increasing temperature at x < 0.5 and decreases at x > 0.5.

Structural distortion behind the nematic superconductivity in Sr x Bi2Se3

An archetypical layered topological insulator Bi

Quantum corrections to the conductivity and anisotropy of the magnetoresistance in Eu-doped Bi 2 Se 3 thin films

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Pb1–xEuxTe alloys (0 ⩽ x ⩽ 1) as materials for vertical-cavity surface-emitting lasers in the mid-infrared spectral range of 4–5 μm

Se

THz lasers based on narrow-gap semiconductors

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Infrared spectroscopy of Bi2Te2Se

becomes superconductive upon doping with Sr, Nb or Cu. Superconducting properties of these materials in the presence of in-plane magnetic field demonstrate spontaneous symmetry breaking: 180

Generation in a microstrip-resonator-stabilized double-barrier resonant tunneling structure

^\circ

Revealing the intrinsic anisotropy of superconducting Sr

-rotation symmetry of superconductivity versus 120