Effect of Barium Codoping on Superconductivity in SrxBi2Se3

JETP Letters - A structural reason for superconductivity in a Cu-, Sr-, or Nb-atom-doped Bi2Se3 topological insulator is still unclear. To understand this reason, a codoping approach has been...     

1H,13C NMR spectral data for α-, β-, and γ-lewisites and identification ofcis,trans, trans-γ-lewisite as a new isomer

The¹H and¹³C NMR spectral parameters of α-, β-, and y-lewisites1–5 were obtained and a new isomer,cis,trans,trans-γ-lewisite5, was isolated and identified on the basis of chemical shifts, relative intensities of the signals, and the intra-chain (³ J _hh ,³ J _ch ) and interchain (³ J _casch ) coupling constants. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1833–1835, October, 1993.     

Specific features of martensitic transformations, microstructure, and mechanical properties of nanostructured shape memory TiNi-TiFe alloys

The microstructure, martensitic transformations, and properties of quasibinary shape memory TiNi-TiFe alloys produced by superrapid melt spinning (SMS) have been studied using transmission electron microscopy and X-ray diffraction analysis and by measuring some properties     

Effect of current modulation depth on the response of single-mode quantum-well heterolasers in the region of 1.5 μm

Numerical simulations are used to study the effect of pump current modulation depth on the response of quantum-well GaInAs–GaInAsP heterolasers at different lasing frequencies within the gain band as a function of the excess above threshold. It is shown that the amplitude-frequency characteristics of these laser emitters generally contain two local maxima. The low frequency maximum usually corresponds to a resonance for the 1/2 subharmonic and the high frequency maximum, to the fundamental. As the modulation depth is increased, the fundamental frequency decreases, while the resonance frequency for the 1/2 subharmonic can change monotonically or not. The behavior found here can be used to develop quantum-well heterolasers with specified modulation parameters.     

Nonlinear Dynamics of a Three‐Wave CO2 Laser with Loss Modulation

The nonlinear dynamics of a CO₂ laser having continuous electrical discharge pumping and loss modulation and generating in three vibrationalrotational lines of the same vibrational band is investigated theoretically. It is shown that it is possible to monitor the time and energy parameters of radiation in rather wide ranges by changing the depth and frequency of modulation and also the relationship between the constant components of losses. The character of the response of the threewave laser in loss modulation in one or two channels at certain parameters is similar to the response of a system with two degrees of freedom. In loss modulation simultaneously in three channels the response is equivalent to the response of a system with one degree of freedom.     

Thermodynamic magnetization of two-dimensional electron gas measured over wide range of densities

We report measurements of ∂m/∂n in Si MOSFET, where m is the magnetization of the two-dimensional electron gas and n is its density. We extended the density range of measurements from well in the metallic to deep in the insulating region. The conditions under which this extension is justified, as well as the corrections that should be made to extract ∂m/∂n properly, are discussed in detail. At low temperatures, ∂m/∂n was found to be strongly nonlinear already in weak magnetic fields, on a scale much smaller than the characteristic scales, expected for interacting two-dimensional electron gas. Surprisingly, this nonlinear behavior exists both in the dielectric, and in the metallic region. These observations, we believe, provide evidence for strong coupling of the itinerant and localized electrons in Si-MOSFET.