Temperature distribution in a repeatedly heated polymer

The conduction problem is presented and solved for a hollow two-layer cylinder having the first layer made of a polymer; the internal boundary moves and there is repeated heating from within. Allowance is made for the heat of reaction in the first layer.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol.18, No. 1, pp.139–145, January, 1970.     

The Influence of Cavity Design on the Linewidth of Near-IR Single-Mode Vertical-Cavity Surface-Emitting Lasers

The studies of the emission linewidth for single-mode near-IR vertical-cavity surface-emitting lasers with an active region based on InGaAs/AlGaAs quantum wells and different optical microcavity design. For low mirror loss, lasers with a 1λ cavity and carrier injection through distributed Bragg reflectors demonstrate a linewidth of 70 MHz and its growth to 110 MHz with increasing mirror loss (corresponding differential of efficiency ～0.65 W/A). The design of the optical cavity with carrier injection through intracavity contacts and low-Q composition Bragg lattices reduces the linewidth to 40 MHz in spite of high mirror loss (corresponding differential efficiency of ～0.6 W/A).     

Formation of Au4Zr nanocrystals in yttria stabilized zirconia in the course of implantation of gold ions

Technical Physics Letters - High-resolution transmission microscopy and optical absorption spectroscopy have been used to examine how metallic nanocrystals (NCs) are formed in the course of...     

Tunnel-coupled InGaAs/GaAs quantum wells: Structure, composition, and energy spectrum

An integrated approach to the analysis of tunnel-coupled InGaAs/GaAs quantum well heterostructures is suggested. In the approach, both experimental and theoretical investigation methods are used. Transmission electron microscopy combined with energy-dispersive X-ray spectrometry is used to determine the spatial distribution of the InGaAs alloy??s composition. The photoluminescence and photoconductivity spectra of the structures are recorded experimentally. In order to interpret the results in more detail, computer simulation of the epitaxial growth is performed. By simultaneously solving the Schr?dinger equation and the Poisson equation, the energy states are calculated for the quantum-confined hetertostructure with initial and real composition profiles. The results of calculations are correlated with the data obtained for interband optical transitions from the analysis of the photoluminescence and photoconductivity spectra. Good agreement between the experimental and theoretical results is gained. The approach suggested in the study provides a means for refining the real geometrical features of the structure, for correlating the spectral results with the real composition profile of the structure, and for correcting the structural and growth parameters to improve the optical characteristics of the structure.     

On Temperature Effects in the Correlation Functions of a Degenerate Electron Plasma

It is shown based on explicit expressions for structural factors and longitudinal and transverse permittivities of degenerate electron plasma within the ideal-gas approximation that temperature effects should be taken into account in these functions to correctly describe the region of small values of wave vectors and frequencies.