Physics and Technology of III–V Heterostructures: Current Status and Trends in the Development

Rapid progress in semiconductor electronics and transition from micro- to nanoelectronics result from progressively smaller dimensions of complementary metal-oxide-semiconductor (CMOS) transistors, development of new single-electron devices, and optical and quantum logical elements. The development of nanotechnologies is an integral part of this process. The present paper reviews the current status of research in molecular-beam epitaxy performed at the Institute of Semiconductor Physics of the Siberian Branch of the Russian Academy of Sciences (Novosibirsk).     

On sets which are removable for quasiconformal space mappings

Siberian Mathematical Journal -     

Mappings slightly changing a fixed cross-ratio

Given a complex number λ ≠ 0, 1, we consider local homeomorphisms of a domain D ? ?? that, in a neighborhood of every point, change slightly (with a given smallness parameter δ) the cross-ratio of tetrads with fixed cross-ratio λ. We prove the quasiconformality of these mappings and obtain bounds for the coefficient of quasiconformality tending to 1 as δ → 0.     

The quasimöbius property on small circles and quasiconformality

We prove that every mapping, without requiring its injectivity or continuity, of a domain of the extended plane which is ω-quasimöbius on sufficiently small circles is locally quasiconformal in this domain with an upper bound on the quasiconformality coefficient depending only on ω. We obtain a similar result for the η-quasisymmetric mappings on small circles (in the Euclidean and chordal metrics), as well as for the mappings satisfying the local Möbius midpoint condition.     

Stabilization of the surface CDW order parameter by long-range Coulomb interaction

We study theoretically formation of two-dimensional (2D) charge density wave (CDW) in a system of conducting chains at the surface of an insulator due to interaction of quasi-1D surface electrons with phonons. We show that the unscreened long-range Coloumb interaction between the charges induced by fluctuations of the CDW phase stabilizes the finite order parameter value at finite temperatures, and thus the long-range order (LRO) exists. In the case of screened Coloumb interaction the phase fluctuations suppress the phase transition, but decay of the order parameter is rather slow, it obeys a power-law 〈Δ^?(r)Δ(0)〉∝r^−γ$〈{\Delta }^{?}(r)\Delta (0)〉\propto r^{-\gamma }$ with small exponent γ$\gamma$.     

Selection of Spectral Variables and Improvement of the Accuracy of Calibration of Temperature by Projection onto Latent Structures Using the Fluorescence Spectra of Yb3+:CaF2

The efficiency of interval methods for selecting variables and the divisive method of interval optimization by a genetic algorithm is considered with the purpose to increase the accuracy of temperature calibration by projection onto latent structures. The fluorescence spectra of Yb³⁺:CaF₂ recorded in the 880–1120 nm band with a resolution of approximately 0.2 nm in the temperature range from 66 to 150°C in 2°C increments are used as an example. The best result for the root-mean-square error of temperature prediction in the test sample (0.45°C) was obtained by interval projection onto latent structures by a combination of moving windows. The use of methods for selecting spectral variables improved more than two times the accuracy of temperature calibration.

     

Moduli of families of curves on a Riemannian manifold

Novosibirsk. Translated from Sibirskii Matematicheskii Zhurnal, Vol. 31, No. 5, pp. 164–166, September–October, 1990.     

Equations and determination of physicochemical properties of ammonium sulfate-nitrate solutions

Theoretical and correlation equations for calculation of multicomponent systems were considered in terms of a previously developed theory of ion-ion interactions in steady-and nonsteady-state processes for the example of ammonium sulfate-nitrate solutions formed from effluent gases of thermal power plants.     

Sono-Photocatalytic Degradation of 4-Clorophenol in Aqueous Solutions

Russian Journal of Physical Chemistry A - The kinetic patterns of oxidative processes involving highly reactive oxygen-containing radicals generated in situ in the aqueous medium affected by...