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An Erratum to this paper has been published: https://doi.org/10.1134/S106378422102016X [ABSTRACT FROM AUTHOR]

The electroluminescence appearing upon pulsed excitation in a solitary p-GaInAsSb/p-InAs typeII (broken-gap) heterostructure is investigated at T = 77 K. It is shown that just as in the case of excitation by a constant current, two emission bands with maxima corresponding to 384 and 311 meV, respectively, are observed in the spectra. The half-widths of the emission bands equal 18-19 meV. Time-resolved spectroscopy is used to evaluate the relaxation time of the nonequilibrium carriers, which amounts to 6-7 µs. The emission spectrum is calculated on the basis of the Kane model, and the radiative recombination time is estimated. The theoretical estimates are in reasonable agreement with experiment. [ABSTRACT FROM AUTHOR]

The theoretical analysis and direct experiments with samples based on n- and p-type porous silicon demonstrate that porous silicon becomes a piezoelectric because of the reduction of the symmetry of the crystal lattice. It is shown that both n and p types of porous silicon have piezoelectric properties. The piezoelectric properties of n-type porous silicon are 2.5 times weaker than the piezoelectric properties of p-type porous silicon at the same porosity because pores in p-type silicon become wider and smoother with an increase in the distance from the surface, whereas pores in n-type porous silicon become narrower and more sinuous. [ABSTRACT FROM AUTHOR]

The sensitivity of nanoporous silicon-based binary mixtures with different oxidizing agents to mechanical effects (impact and friction) has been experimentally determined on K-44-1 and K-44-3 shock machines. The results obtained are compared with the data on the sensitivity of regular initiating explosives. [ABSTRACT FROM AUTHOR]

Laser and electron-beam initiation of the combustion process of energy-saturated composite films were studied. Composites were produced from porous silicon, a fluorine-containing polymer, and graphene. It is shown that the impact of a high-current electron beam of nanosecond duration does not lead to the excitation of the combustion process. Moreover, the process of film combustion during laser initiation is accompanied in some cases by the appearance of a zone of secondary flame and white smoke. [ABSTRACT FROM AUTHOR]

The mechanism of singlet-oxygen generation on the surface of photoexcited nanoporous silicon has been theoretically analyzed. It is shown that the mechanism of singlet-oxygen generation is based on nonradiative energy transfer from nanoporous silicon to an oxygen molecule according to the Dexter exchange mechanism. An analytical expression is obtained, and the probability of energy transfer from nanoporous silicon to an oxygen molecule is numerically estimated. It is shown that its numerical value, on the order of ~(103–104) s–1, is in good agreement with the experimental data. [ABSTRACT FROM AUTHOR]

A brief review and results of experimental investigation of the properties of energy-saturated nanoporous silicon-based composites are presented. Various types of oxidants used in the composites are examined. Calcium perchlorate has been used as an oxidant. The energy-saturated composite under study is shown to exceed in several parameters the primary explosive, mercury fulminate and brisant explosive, RDX. [ABSTRACT FROM AUTHOR]

The method of determination combustion rate of powdered porous silicon with limited space is presented. The values of the combustion rates of porous silicon are close to the values of the rates of explosives. [ABSTRACT FROM AUTHOR]

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 capabilities of metalorganic vapor-phase epitaxy (MOVPE) in fabrication of structures with thin (1–2 nm) alternating InAs/GaSb layers on a GaSb substrate are studied. The characteristics of these structures were examined using transmission electron microscopy and methods of photo- and electroluminescence. It was found that two GaInAsSb solid solutions of different compositions were formed in the active regions of structures in the given growth conditions. The fabricated system was characterized by an emission wavelength of 4.96 μm at a temperature of 77 K. The results reveal new opportunities for bandgap engineering of semiconductor structures based on InAs/GaSb, which are designed for optoelectronic devices operating in the infrared range, provided by MOVPE. [ABSTRACT FROM AUTHOR]

Expressions for the Auger- and radiative-recombination rates are derived in terms of Kane's model for materials with a band-gap width close to the spin-orbit splitting energy, which is the case for InAs, InAsSb solid solutions, etc. Our results are compared with simplified expressions for recombination rates, frequently used in publications. It is shown that the nonparabolicity of the electronic structure should be taken into account in calculations of the recombination rates. As an example, the temperature dependences of the charge-carrier lifetimes governed by radiative and non-radiative processes are calculated for InAsSb solid solutions. [ABSTRACT FROM AUTHOR]

The first results showing the possibility of manufacturing InAs/GaSb superlattices by the metal-organic chemical vapor deposition (MOCVD) method are presented. The possibility of manufacturing heterostructures with an InAs/GaSb strained superlattice with layer thicknesses of 2–4 nm is experimentally demonstrated. The 77-K electroluminescence spectra of the structures show a long-wavelength peak at around 5.0 μm (0.25 eV). This peak is probably associated with the strained superlattice because solid solutions that could form on the basis of composite compounds do not provide this carrier-recombination energy. [ABSTRACT FROM AUTHOR]

A theoretical analysis of the mechanism of generation of singlet oxygen in the presence of photoexcited nanoporous silicon is presented. It is demonstrated that the mechanism of generation of singlet oxygen is based on nonradiative energy transfer from nanoporous silicon to an oxygen molecule by the exchange mechanism. An analytical expression of the probability of energy transfer from nanoporous silicon to an oxygen molecule is obtained, and a numerical estimate of this process is given. The numerical estimation is of the order of 103-104 s-1, a value that agrees rather well with the experiment. [ABSTRACT FROM AUTHOR]

An experimental study of the influence exerted by powdered shungite additives with particle size of 30–35 μm on the threshold characteristics of the breakdown voltage in ammonium perchlorate is reported. The effects of powdered shungite and graphite additives are compared. [ABSTRACT FROM AUTHOR]