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We study in detail the mechanisms of radiative and Auger recombination in type-I and type-II heterostructures based on III–V narrow-gap materials. The presence of a heterointerface fundamentally changes the nature of these recombination processes with respect to the bulk material differently, depending on the type of heterojunction. Studying the electroluminescence of type-I and type-II light-emitting diode (LED) heterostructures based on InAsSb/InAs(Sb,P) quantum wells is presented. An increase in the relative efficiency of radiative recombination in the type-II heterostructure due to the suppression of Auger recombination favors the formation of intense stimulated emission in such heterostructures at low temperatures (4.2–70 K). [ABSTRACT FROM AUTHOR]

The results of a study in the temperature range 4.2–300 K of the current–voltage characteristics of light emitting diode (LED) heterostructures with an active region based on InAsSb solid solutions and InAsSb/InAs or InAsSb/InAsSbP quantum wells (QWs) are presented. The carrier-transport mechanisms depending on the temperature and heterostructure design are determined. It is shown that charge transport across the heterostructures is governed by the diffusion and recombination mechanisms at temperatures close to 300 K; in the temperature range 4.2–77 K, the contribution of the tunneling mechanism is observed. For an InAs/InAs/InAs0.15Sb0.31P0.54 heterostructure, an additional carrier-transport channel is observed. It is shown that the presence of 108 InAs0.88Sb0.12/InAs QWs in the active region leads to an increase in leakage currents across the heterojunction in the whole temperature range, which is likely related to carrier tunneling. [ABSTRACT FROM AUTHOR]

The results of the study of optical and structural properties of epitaxial InAs layers grown on an n-InAs substrate, and spectral and electrical properties of light-emitting diode (LED) heterostructures with an InAs active layer and various design and chemical composition of barrier layers are presented; the properties of heterostructures were studied in the temperature range 4.2−300 K. A significant influence of the degree of substrate doping and the properties of heterointerfaces on the form of emission spectra and power characteristics of heterostructures is shown. The mechanisms of the carrier transport are studied, and the prevalence of the diffusion component of the current at temperatures above 200 K and the presence of the tunneling component at lower temperatures are shown. [ABSTRACT FROM AUTHOR]

The results of comparative studies of the optical and structural properties of Hg0.7Cd0.3Te bulk crystals and epitaxial films grown by various methods are presented. The data of photoluminescence studies performed in the temperature range 4.2–300 K showed the similarity of the optical properties of different samples and indicated a significant disordering of the solid solution. According to X-ray diffraction data, however, the scale of the disordering was not directly related to the structural quality of the material. The prospects for using the material grown by various methods in optoelectronics applications are discussed. [ABSTRACT FROM AUTHOR]

The electroluminescent characteristics of the InAs/InAs1–ySby/InAsSbP asymmetric light-emitting diode heterostructures with high InSb mole fraction in the active region (y > 0.09) in the temperature range 4.2–300 K have been studied. Stimulated emission was achieved in the wavelength range 4.1–4.2 μm at low temperatures (T < 30 K). It was found that the electroluminescence spectra were formed as a result of the superposition of contributions from different channels of radiative recombination of charge carriers near the type II heterointerface. The effect of the quality of the type II InAsSb/InAsSbP heterojunction on the radiative interface transitions with an increase in the content of InSb in the ternary solid solution is considered. [ABSTRACT FROM AUTHOR]