scholarly journals Current state and prospects of detectors in the terahertz range. Part 2. Heterodyne detection of terahertz radiation

2021 ◽  
Vol 9 (6) ◽  
pp. 499-512
Author(s):  
Nikolay Kulchitsky ◽  
Arkadii Naumov ◽  
Vadim Startsev ◽  
Mikhail Dem’yanenko
Keyword(s):  
Terahertz Radiation ◽  
Recent Progress ◽  
Direct Detection ◽  
Radiation Detectors ◽  
Terahertz Range ◽  
Heterodyne Detection ◽  
Advantages And Disadvantages ◽  
Current State ◽  
Range Part ◽  
Physical Phenomena

The paper discusses the problems associated with the development of technology for terahertz radiation detectors. The main physical phenomena and recent progress in various methods of detecting terahertz radiation (direct detection and heterodyne detection) are considered. Advantages and disadvantages of direct detection sensors and sensors with heterodyne detection are discussed. In part 1, a number of features of direct detection are considered and some types of terahertz direct detection detectors are described. Part 2 will describe heterodyne detection and continue to describe some types of modern photonic terahertz receivers.

scholarly journals Current state and prospects of detectors in the terahertz range Part 1. Direct detection of terahertz radiation

2021 ◽  
Vol 9 (1) ◽  
pp. 68-85
Keyword(s):  
Terahertz Radiation ◽  
Direct Detection ◽  
Radiation Detectors ◽  
Terahertz Range ◽  
Heterodyne Detection ◽  
Advantages And Disadvantages ◽  
Current State ◽  
Range Part ◽  
Physical Phenomena

The paper discusses the problems associated with the development of technology for terahertz radiation detectors. The main physical phenomena and recent pro-gress in various methods of detecting terahertz radiation (direct detection and het-erodyne detection) are considered. Advantages and disadvantages of direct detec-tion sensors and sensors with heterodyne detection are discussed. In part 1, a number of features of direct detection are considered and some types of terahertz direct detection detectors are described. Part 2 will describe heterodyne detection and continue to describe some types of modern photonic terahertz receivers.

scholarly journals Halide lead perovskites for ionizing radiation detection

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Haotong Wei ◽  
Jinsong Huang
Keyword(s):  
Ionizing Radiation ◽  
High Performance ◽  
Direct Detection ◽  
Low Cost ◽  
Radiation Detection ◽  
Radiation Detectors ◽  
Solution Processes ◽  
Current State ◽  
X Ray Imaging ◽  
Halide Perovskites

Abstract Halide lead perovskites have attracted increasing attention in recent years for ionizing radiation detection due to their strong stopping power, defect-tolerance, large mobility-lifetime (μτ) product, tunable bandgap and simple single crystal growth from low-cost solution processes. In this review, we start with the requirement of material properties for high performance ionizing radiation detection based on direct detection mechanisms for applications in X-ray imaging and γ-ray energy spectroscopy. By comparing the performances of halide perovskites radiation detectors with current state-of-the-art ionizing radiation detectors, we show the promising features and challenges of halide perovskites as promising radiation detectors.

scholarly journals Classification and analysis of measuring transducers of intensity (induction) of alternating magnetic fields

2021 ◽  
pp. 82-93
Author(s):  
Yurii Bobkov
Keyword(s):  
Magnetic Fields ◽  
Magnetic Measurements ◽  
Advantages And Disadvantages ◽  
Current State ◽  
Primary Measuring ◽  
Wide Range ◽  
The Right ◽  
Physical Phenomena ◽  
Alternating Magnetic Fields

The current state of technology is characterized by the mass use of electricity, the use of various electrical, electronic and radio devices. This causes expansion of magnetic measurements and the need to develop new highly sensitive measuring equipment for a wide range of frequencies. One of its main elements, that largely determines the accuracy, frequency and dynamic ranges, are the primary measuring sensors of strength (induction) of alternating magnetic fields. Many works have been devoted to the analysis and development of various sensors of strength (induction) of magnetic fields. At the same time, it can be noted the lack of a systematic approach to the measurement of alternating magnetic fields. The problem of the general classification of methods of measurement of alternating magnetic fields and, accordingly, primary measuring sensors of strength (induction) of alternating magnetic fields is not solved. In most cases, separate issues of measuring alternating magnetic fields and certain types of sensors are considered. That does not allow obtaining a holistic picture in this area and make the right choice of direction for solving assigned tasks. The comprehensive analysis of methods of measuring alternating magnetic fields was carried out in this work. Based on it, the classification of primary measuring sensors of strength (induction) of alternating magnetic fields, on the physical principles of transformation was proposed. Accordingly, the available measuring sensors of alternating magnetic fields following to the group of used physical phenomena can be divided into: magnetomechanical, induction, galvanomagnetic, quantum, magneto-optical and photomagnetic. Depending on the characteristics of each of these phenomena, separate measurement methods and types of measuring sensors were highlighted. The current state of development of each of the types of measuring sensors of strength of alternating magnetic fields was analyzed, their advantages and disadvantages were determined, the limits of dynamic and frequency ranges, the maximum values of errors were outlined. The obtained results allow to significantly simplify and reduce the time of choosing the necessary method of strength (induction) of alternating magnetic fields measuring and to choose the necessary type of measuring sensor to effectively solve the tasks.

scholarly journals Photothermal, Photoelectric, and Photothermoelectric Effects in Bi-Sb Thin Films in the Terahertz Frequency Range at Room Temperature

Photonics ◽  
2021 ◽  
Vol 8 (3) ◽  
pp. 76
Author(s):  
Mikhail K. Khodzitsky ◽  
Petr S. Demchenko ◽  
Dmitry V. Zykov ◽  
Anton D. Zaitsev ◽  
Elena S. Makarova ◽  
...  
Keyword(s):  
Thin Films ◽  
Terahertz Radiation ◽  
Room Temperature ◽  
Voltage Drop ◽  
Radiation Detection ◽  
Radiation Detectors ◽  
Thz Radiation ◽  
Terahertz Frequency ◽  
Frequency Range ◽  
Terahertz Frequency Range

The terahertz frequency range is promising for solving various practically important problems. However, for the terahertz technology development, there is still a problem with the lack of affordable and effective terahertz devices. One of the main tasks is to search for new materials with high sensitivity to terahertz radiation at room temperature. Bi1−xSbx thin films with various Sb concentrations seem to be suitable for such conditions. In this paper, the terahertz radiation influence onto the properties of thermoelectric Bi1−xSbx 200 nm films was investigated for the first time. The films were obtained by means of thermal evaporation in vacuum. They were affected by terahertz radiation at the frequency of 0.14 terahertz (THz) in the presence of thermal gradient, electric field or without these influences. The temporal dependencies of photoconductivity, temperature difference and voltage drop were measured. The obtained data demonstrate the possibility for practical use of Bi1−xSbx thin films for THz radiation detection. The results of our work promote the usage of these thermoelectric materials, as well as THz radiation detectors based on them, in various areas of modern THz photonics.

Recent Progress in TlBr Radiation Detectors

2006 ◽  
Author(s):  
Yuri Dmitriev ◽  
Hadong Kim ◽  
William Higgins ◽  
Leonard Cirignano ◽  
Purushottam Dokhale ◽  
...  
Keyword(s):  
Recent Progress ◽  
Radiation Detectors

Rating assessment of economic security of municipalities in the region

2021 ◽  
Vol 97 (4) ◽  
pp. 72-81
Author(s):  
M. S. Syupova ◽  
Keyword(s):  
Local Governments ◽  
Economic Condition ◽  
Economic Security ◽  
Management Tool ◽  
Existing Problems ◽  
Advantages And Disadvantages ◽  
Current State ◽  
Regional Authorities ◽  
Negative Factors

Ensuring the economic security of municipalities is one of the key conditions for stable socio-economic de-velopment of the region. Recently, intraregional differentiation of territories has been growing, which increases the risk of the formation of negative factors that reduce the quality of life of the population. In order to neutralize and prevent acute social and economic problems, constant monitoring of the current state of the municipal econ-omy is necessary. As such a management tool, a rating assessment of the economic security of municipalities in the region can be used. The ranking of territories allows you to visualize the relative advantages and disadvantages of the development of territories. In addition, a systematic comparative analysis of controlled socio-economic pa-rameters will allow regional authorities to evaluate the results of the activities of local governments and improve the effectiveness of regional socio-economic policy. The article proposes a methodology for rating the economic security of municipalities, during which it is possible to visually assess the depth of the threats studied at the level of each territory. To this end, the proposed methodology is based on a system of indicators that identify the main problem areas of the socio-economic condition of the territories. To form the rating, the studied indicators are normalized and integral indices characterizing the level of economic security of municipalities are calculated. The methodology proposes criteria for assessing the level of municipal economic security (high; above average; aver-age; crisis; critical). According to the results of the study, a rating of municipal districts of the Khabarovsk Terri-tory was compiled. The study showed that the territories of the region are characterized by an unstable socio-economic condition. The leading positions in the rating are occupied by areas with an average level of economic security. Most municipal districts of the region have a crisis level of economic security, which provides for the de-velopment of a set of measures aimed at eliminating existing problems.

The role of motivation in talent selection and ­development in competitive sport

2021 ◽  
Keyword(s):  
Measurement Instrument ◽  
Psychological Characteristics ◽  
Advantages And Disadvantages ◽  
Current State ◽  
Talent Selection ◽  
Comprehensive Picture ◽  
Performance Development ◽  
The Right

The early and long-term development of promising young athletes is a decisive factor in being internationally competitive in top-level sports. Among the multitude of talent criteria suggested in the literature, motivation plays a prominent role in the area of psychological characteristics. It is recognised in practice and research as a relevant criterion for performance development across all sports. This article provides an overview of the current state of talent research in the field of motivation. First, the most common theories of motivation in competitive sports are described, then different measurement methods and their advantages and disadvantages as well as the predictive value of motivation for athletic performance are discussed. Finally, implications for practice are suggested. It can be summarised that motivation in sport is conceptualised and operationalised in different ways and that the decision for the right measurement instrument depends on the goal of the assessment. To get a comprehensive picture of an athlete’s motivational status, it is useful to assess several aspects of motivation through different methods.

scholarly journals Performance of Multibeam Very High Throughput Satellite Systems Based on FSO Feeder Links with HPA Nonlinearity

2020 ◽  
Author(s):  
Emna Zedini ◽  
Abla Kammoun ◽  
Mohamed-Slim Alouini
Keyword(s):  
Outage Probability ◽  
High Throughput ◽  
Direct Detection ◽  
Satellite Communications ◽  
Ergodic Capacity ◽  
Heterodyne Detection ◽  
High Signal ◽  
Free Space Optical ◽  
Asymptotic Results ◽  
Very High

Due to recent advances in laser satellite communications technology, free-space optical (FSO) links are presented as an ideal alternative to the conventional radio frequency (RF) feeder links of the geostationary satellite for next generation very high throughput satellite (VHTS) systems. In this paper, we investigate the performance of multibeam VHTS systems that account for nonlinear high power amplifiers at the transparent fixed gain satellite transponder. Specifically, we consider the forward link of such systems, where the RF user link is assumed to follow the shadowed Rician model and the FSO feeder link is modeled by the Gamma-Gamma distribution in the presence of beam wander and pointing errors where it operates under either the intensity modulation with direct detection or the heterodyne detection. Moreover, zero-forcing precoder is employed to mitigate the effect of inter-beam interference caused by the aggressive frequency reuse in the user link. The performance of the system under study is evaluated in terms of the outage probability, the average bit-error rate (BER), and the ergodic capacity that are derived in exact closed-forms in terms of the bivariate Meijer's G function. Simple asymptotic results for the outage probability and the average BER are also obtained at high signal-to-noise ratio.

scholarly journals APPLICATION OF COMPUTER MODELING POSSIBILITIES IN THE STUDY OF PHYSICAL MODELS

2021 ◽  
pp. 25-34
Author(s):  
Pavlo Kindrat ◽  
Ihor Voitovych ◽  
Vladimir Mashchenko
Keyword(s):  
Physics Education ◽  
Mathematical Problem ◽  
Computer Models ◽  
Ideal Gas ◽  
Educational Process ◽  
Physical Models ◽  
Professional Activities ◽  
Advantages And Disadvantages ◽  
Virtual Laboratories ◽  
Physical Phenomena

The advantages and disadvantages of using a virtual laboratory and computer models in the educational process in physics are identified. The expediency of using virtual laboratories and computer models in the context of mixed physics education is substantiated. To teach future physics teachers to create and use computer models of physical phenomena and processes is carried out in a professionally oriented author's course "Methods of using computer technology in professional activities." The stages of development of a physical model for the formulation of a mathematical problem are described and the implementation on the example of development and use of the program "Dynamic model of an ideal gas" is shown.

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