Publications by authors named "V V Preobrazhenskii"
Article Synopsis
- - This study explored the creation and structural characteristics of self-assembled GaSb/AlP quantum dots (SAQDs) using experimental techniques, focusing on their growth through molecular beam epitaxy on GaP and GaP/Si substrates.
- - The research found that while SAQDs exhibit almost complete plastic strain relaxation, dislocations formed in GaP substrates significantly decrease luminescence efficiency, unlike those on GaP/Si substrates which maintain performance likely due to different types of dislocations.
- - The GaP/Si-based SAQDs have a unique type II energy spectrum with an indirect bandgap, contributing to a long potential charge storage time of over 10 years, indicating their promise for applications in universal memory cells.
Article Synopsis
- - The study explores using low-temperature (LT) GaAs layers as a method to reduce dislocation defects in GaAs/Si heterostructures by investigating the effects of these layers and post-growth annealing.
- - Results showed that introducing LT-GaAs layers and performing cyclic annealing significantly reduced dislocation density, surface roughness, and non-radiative recombination centers in the GaAs/Si regions.
- - The improvements in the quality of near-surface GaAs layers are attributed to elastic deformations causing dislocation line bending and gallium vacancies diffusing into the GaAs layers, making these heterostructures suitable for high-quality light-emitting applications with quantum dots.
AlGaAsSb and AlGaAs films as thick as 1 μm with Al content as high as 60% were successfully grown by low-temperature (200 °C) MBE. To overcome the well-known problem of growth disruption due to a high aluminum content and a low growth temperature, we applied intermittent growth with the temperature elevation to smooth out the emerging roughness of the growth front. Post-growth annealing of the obtained material allowed us to form a developed system of As or AsSb nanoinclusions, which occupy 0.
View Article and Find Full Text PDFA high-power, diode-pumped, semiconductor saturable absorber mode-locked Yb(5%):KGW bulk laser was demonstrated with high optical-to-optical efficiency. Average output power as high as 8.8 W with optical-to-optical efficiency of 37.
View Article and Find Full Text PDF[The estimation of the effectiveness of early rehabilitation of the athletes practicing different sports after the knee injury with the use of specific simulators].
Vopr Kurortol Fizioter Lech Fiz Kult
November 2013
There are yet no optimal criteria to be applied in rehabilitative sports medicine for the estimation of the restoration of the athletes' physical conditions to enable them to return to their professional activities. The primary objective of the present study was to develop specific methods for the assessment of the physical performance of the athletes safe enough for the use at any stage of testing and sufficiently informative to give idea of the athlete's condition. To this effect, we compared the effectiveness of various testing procedures specific for different sports.
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