The energy spectra of the mercury vacancy, the most common acceptor in HgCdTe material, is studied via numerical calculations and low temperature photoconductivity (PC) measurements of 'vacancy-doped' HgCdTe films with low cadmium content. Since the Hg vacancy is known to be a double acceptor, the model for the helium atom was adopted for degerate valence band of zinc blende semiconductors to classify the observed PC bands. This approach provides a fairly good description of the photoionization of both neutral and singly-ionized vacancy when the central cell potential is taken into account.

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Mercury vacancies, acting as double acceptors, are the dominant point defects in ternary HgCdTe alloys. Though HgCdTe is one of the leading materials in infrared optoelectronics, the energy spectra of the vacancies are still a matter of some debate. This work investigated the rates at which holes are captured to a singly ionized mercury vacancy via acoustic phonon emission in narrow-gap Hg1−xСdxTe with technologically relevant x~0.22. Combined with the calculated rates of intracenter transitions, the data allow one to predict the most pronounced optical transitions in the emission spectrum of a double-charged acceptor. The results are sustained by the photoluminescence spectroscopy in the terahertz domain, allowing one to identify the emission band that is related to neutral vacancies.

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The development of the territory of Moscow has led to the need for a survey of water bodies and inventory of existing hydraulic structures, a thorough assessment of their technical condition, typifying the main types of structures, and determining their functional features. To solve these tasks, we used methods of field expedition survey, and analytical calculations of hydraulic structures, statistical methods of information processing, and analysis of available cartographic and technical documentation. A quantitative and qualitative analysis of the state of hydraulic structures located on the territory of New Moscow and their operating conditions was performed; the current level of their safety was assessed. It is proved that it is necessary to create a unified information database for all water bodies and hydraulic structures that have passed the survey, as well as to develop a simplified form of the act of pre-Declaration inspection of structures for which there is no functional and design information. It is shown that it is necessary to develop a plan of measures to ensure the safety of hydraulic structures without registered property rights.

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