Compact and cost-effective spectrometers and imaging systems in the terahertz (THz) frequency range based on optical-THz photoconductive converters of ultrashort laser pulses (photoconductive antennas PCAs) are actively being developed and widely used to solve fundamental and applied problems in a variety of fields of science and technology. This high activity of research and development is associated with the PCAs' reliability and compact size, the easy scalability of a single element to 1D and 2D arrays, and PCAs' ability to provide a wide spectral range and high dynamic range of recorded THz signals without cooling. Recently, systems for multi-pixel detection of THz radiation based on matrix PCA detectors, designed to greatly increase the speed of THz imaging, have been of particular interest. This review presents the latest trends in the development of PCA-based THz devices, PCA-based methods of THz pulsed spectroscopy and imaging, as well as alternative approaches to THz pulse recording and THz imaging.

In memory of Aleksandr Fedorovich Andreev, Dmitriev V.V., Kagan M.Yu., Kamenskii V.G., Kats E.I., Kveder V.V., Kreines N.M., Lebedev V.V., Marchenko V.I., Melnikovsky L.A., Smirnov A.I., Suslov I.M., Fomin I.A., Edel’man V.S.

20 ×ÇÄÓÂÎâ 2023 Å. Р94-Ï ÅÑAEÖ ÉËÊÐË ÔÍÑÐÚÂÎÔâ ÄÞAEÂáÜËÌÔâ ÔÑÄÇÕÔÍËÌ Ë ÓÑÔÔËÌÔÍËÌ ×ËÊËÍ-ÕÇÑÓÇÕËÍ, ÂÍÂAEÇÏËÍ ²ÑÔÔËÌ-ÔÍÑÌ ÂÍÂAEÇÏËË ÐÂÖÍ (²¡¯) ³ÇÏÈÐ ³ÑÎÑÏÑÐÑÄËÚ ¤ÇÓÛÕÇÌÐ, ÄÐÈÔÛËÌ ×ÖÐAEÂÏÇÐÕÂÎßÐÞÌ ÄÍÎÂAE Ä ÂÕÑÏÐÖá ×ËÊËÍÖ, ×ËÊËÍÖ ÚÂÔÕËÙ Ë ÂÔÕÓÑ×ËÊËÍÖ.³ÇÏÈÐ ³ÑÎÑÏÑÐÑÄËÚ ÓÑAEËÎÔâ Ä Å. •ÂÓÃËÐÇ (®ÂÐßÚÉÖÓËâ) Ä ÔÇÏßÇ ÔÑÄÇÕÔÍËØ ÅÓÂÉAEÂÐ.£ 1936 Å. ÑÐ ÄÏÇÔÕÇ Ô ÔÇÏßÈÌ ÒÇÓÇÇØÂÎ Ä ®ÑÔÍÄÖ.£ 1937 ë 1938 ÅÅ.ÇÅÑ ÓÑAEËÕÇÎË ÃÞÎË ÓÇÒÓÇÔÔËÓÑÄÂÐÞ (ÒÑÎÐÑÔÕßá ÓÇÂÃËÎËÕËÓÑÄÂÐÞ Ä 1955 ë 1956 ÅÅ.).³ ÄÑÔßÏË ÎÇÕ ³ÇÏÈÐ ³ÑÎÑÏÑÐÑÄËÚ ÄÑÔÒËÕÞÄÂÎÔâ ÃÂÃÖÛÍÑÌ ¡.ª.®ÇÐAEÇÎÇÄËÚ, ÓÂÃÑÕÂÄÛÇÌ ×ÇÎßAEÛÇÓÑÏ Ä ÊÂ-ÄÑAEÔÍÑÏ ÏÇAEÒÖÐÍÕÇ.£ 1946 Å. ³ÇÏÈÐ ³ÑÎÑÏÑÐÑÄËÚ ÊÂÍÑÐÚËÎ Ô ÊÑÎÑÕÑÌ ÏÇ-AEÂÎßá ÔÓÇAEÐáá ÛÍÑÎÖ Ë ÃÞÎ ÒÓËÐâÕ Ð ×ËÊËÚÇÔÍËÌ ×ÂÍÖÎß-ÕÇÕ ®ÑÔÍÑÄÔÍÑÅÑ ÅÑÔÖAEÂÓÔÕÄÇÐÐÑÅÑ ÖÐËÄÇÓÔËÕÇÕ ËÏ. ®.£.Ñ-ÏÑÐÑÔÑÄ (®¤µ).£ 1951 Å. ÑÐ ÑÍÑÐÚËÎ ×ËÊ×ÂÍ ®¤µ Ë ÃÞÎ ÐÂÒÓÂÄÎÇÐ ÒÑ ÓÂÔÒÓÇAEÇÎÇÐËá РÓÂÃÑÕÖ ÖÚËÕÇÎÇÏ Ä ÔÓÇAEÐáá ÛÍÑÎÖ ÔÇΠ¢ÇÎÑÖÔÑÄÑ ¬ÂÎÖÉÔÍÑÌ ÑÃÎÂÔÕË, ØÑÕâ ÓÖÍÑÄÑAEË-ÕÇÎß ÇÅÑ AEËÒÎÑÏÐÑÌ ÓÂÃÑÕÞ ÒÓÑ×

We discuss the influence of hydrogenation on the electronic properties of dislocations in crystalline Si. The results are briefly reviewed of DL/TS, EPR, HF conductivity, photoluminescence and hydrogen exodiffusion studies.

Oleg Igorevich Korablev (on his 60th birthday), Balega Yu.Yu., Bisikalo D.V., Bykov A.M., Zheleznyakov V.V., Zelenyi L.M., Kveder V.V., Krymskii G.F., Marov M.Ya., Rozanov N.N., Stepanov A.V., Cherepashchuk A.M., Shustov B.M.

Вадим Вениаминович Бражкин (к 60-летию со дня рождения), Арсеев П.И., Виноградов Е.А., Кведер В.В., Литасов К.Д., Муртазаев А.К., Пудалов В.М., Рыжов В.Н., Садовский М.В., Стрельцов С.В., Сурис Р.А., Суровцев Н.В., Щербаков И.А.

Сергей Николаевич Багаев (к 80-летию со дня рождения), Балега Ю.Ю., Жеребцов Г.А., Кульчин Ю.Н., Кведер В.В., Латышев А.В., Литвак А.Г., Матвеев В.А., Месяц Г.А., Нигматулин Р.И., Ратахин Н.А., Сергеев А.М., Шалагин А.М.

Памяти Николая Николаевича Сибельдина, Арсеев П.И., Горбацевич А.А., Демихов Е.И., Кведер В.В., Колачевский Н.Н., Красильник З.Ф., Крохин О.Н., Кукушкин И.В., Месяц Г.А., Сурис Р.А., Тимофеев В.Б., Щербаков И.А.

Modern trends in solar energy development and "defect engineering" features for multi-crystalline silicon based solar cells manufacturing are discussed.

Professor Alexander A. Kaminskii, known for his highly influential publications and books on laser crystals and related materials, passed away on 29 October 2019, shortly after publishing his last papers in the same year. Alexander A. Kaminskii was born in Moscow, USSR, on 23 October 1934. The family went to Kazan, which is located on the banks of the Volga River, and young Alexander entered Kazan Aviation University. Since he was always striving to engage in scientific activities, he dreamed to study at Lomonosov Moscow State University. When the government politics had changed, he managed to move there. He found his way to become a prominent researcher and professor at internationally prestigious universities and institutes. In addition, he was appointed Corresponding Member of the Russian Academy of Sciences (RAS) and was head of a laboratory in the Shubnikov Institute of Crystallography in Moscow. Prof. Kaminskii was a pure scientist, who liked to express his research results on physical material quantities, preferably optical wavelengths by precise numbers and units. He was not much interested in organizational tasks. However, he could also be humorous and charming. He established international contacts to France, Germany (East andWest), Japan, China, Poland, Spain and the United States of America, amongst others. He was a member of the Russian Delegation to the General Assemblies of International Union of Pure and Applied Physics (IUPAP) and the International Council for Science (ICSU). As a Vice-President at Large of IUPAP from 2008 to 2014 he played a key role in ensuring that Russia was actively involved in the work of the Union and its Commissions. In addition, he was a member of the Optical Society (OSA). We consider his contacts to the science community of democratic countries an important contribution to tearing down the Iron Curtain, symbolized by the Berlin Wall. Prof. Kaminskii was among the first to recognize the power of empirical application of the Judd-Ofelt theory of crystal-fieldinduced radiative transition intensities among the energy levels of trivalent rare earth ions (RE3þ) doped into dielectric crystals. Along with colleagues, especially Marvin Weber, Francois Auzel, Renata Reisfeld, Alexandra M. Tkachuk, and others at the Lawrence Livermore National Laboratory, he created, and organized in his later books, a comprehensive database of Judd-Ofelt parameters, assisting researchers in the guided search for, and the interpretation of the comparative performances of many interesting rare earth ion-doped laser crystals, such as neodymium-doped laser crystals. Later, this methodology was beneficially applied to the purposeful development of laser glasses doped with neodymium ions in support of inertial confinement fusion research, and to glass fibers doped with erbium ions in support of optical communication. His cooperation with the later Institute of Optics and Atomic Physics of the Technical University Berlin (TUB) commenced during a workshop in Erice, Italy. Afterwards, he visited Berlin many times and in turn he invited Prof. H. J. Eichler and colleagues to his laboratory and other main institutes in Moscow, Novosibirsk, and Tbilisi, Georgia. A first joint paper on “Spectroscopic and laser properties of Er3þ-doped monoclinic BaY2F8 single crystals” appeared in July 1990. In the following decade, articles on lamp and diode pumped solid state lasers were published. Prof. Kaminskii was always interested in search of efficient multifunctional laser elements. At first, these were crystals for simultaneous laser and second harmonic generation, later for laser generation and stimulated Raman scattering. Around the turn of the century, A. A. Kaminskii and H. J. Eichler started a very fruitful cooperation on stimulated Raman scattering (SRS) in crystals. First SRS experiments were done in the USA but there had always been a long tradition in Raman scattering in Russia where spontaneous scattering was observed first by Landsberg and Mandelstam, called “kombinatsionnoe” scattering. A picosecond Nd:YAG laser to pump more than 100 different crystal types provided by Prof. Kaminskii and international colleagues was employed. Around 3000 SRS emission lines have been discovered and assigned to the underlying nonlinear optical processes in the investigated crystals by intense pump laser pulses in the ultraviolet, visible and infrared spectral regions. The observed SRS lines cover the spectral range from 0.2 μm to 2 μm with less than 2 nm spacing, so that the studies allow building Raman lasers at nearly arbitrary wavelengths which are difficult to access with conventional solid state laser sources. The results support applications inmodern laser technology. Frequency chains and ultrashort light pulses can be generated. More than 150 journal articles were published on SRS experiments which were carried out at TUB mainly with former Ph.D. students Dirk Grebe, Julian Findeisen, Oliver Lux, Hanjo Rhee and Chris Scharfenorth. Prof. Kaminskii initiated most of the articles and was strongly involved in the analysis and publication of the results. The close cooperation was honored by the German Humboldt Foundation which supported him to do research and to teach as a full Professor at the Optical DOI: 10.1002/pssa.202000129 OBITUARY

Александр Александрович Каплянский (к 90-летию со дня рождения), Агранович В.М., Александров Е.Б., Багаев С.Н., Грехов И.В., Забродский А.Г., Иванов С.В., Ивченко Е.Л., Кведер В.В., Новиков Б.В., Сурис Р.А., Тимофеев В.Б., Щербаков И.А.

Impact of iron atoms on electronic properties of FZ n-Si containing dislocations introduced by plastic deformation is studied using deep level transient spectroscopy (DLTS) and laser beam induced current (LBIC). Amplitudes of dislocation related DLTS peaks "C1" at 201 K and "D" at 247 K increase significantly after diffusing iron at 900 degrees C in the samples quenched after diffusion. DLTS and LBIC data correlate nicely showing a significant increase of electron-hole recombination at dislocations in the same samples. We therefore suppose that the DLTS peaks "C1" and "D" observed earlier in many publications can be partially related to iron at dislocations.

By using deep level transient spectroscopy (DLTS) and light beam induced current (LBIC) the behavior of chromium atoms in float‐zone n‐Si in the presence of dislocations and as‐grown vacancy complexes has been investigated. It was found that reactions of interstitial chromium atoms with dislocations and with as‐grown nitrogen–vacancy complexes reduce significantly the nucleation barrier for the formation of chromium‐silicide precipitates so that nearly all Cr atoms are collected into the precipitates even in quenched samples. These nano‐precipitates are very active in electron‐hole recombination and give a very broad DLTS signal related to deep donor electronic states in the bandgap of silicon.

In this paper we present experimental results of investigations of vacancy complexes Vxtrail (“trail defects”), generated by moving dislocations in silicon. For detection of Vxtrail defects we used their reactions with atoms of transition metals. LBIC and DLTS methods were used for investigations of electrically active defects. We show that the probability of generation of Vxtrail defects by a moving dislocation decreases with increasing temperature of plastic deformation with activation energy of about 2.3 eV.

Vladislav Borisovich Timofeev, a Full Member of the Russian Academy of Sciences (RAS). Vladislav Borisovich is an outstanding experimental physicist, well known for his scientific results in the field of semiconductors and solid state physics. He has published over 200 scientific papers, including 16 reviews and two monographs. V B Timofeev graduated from the Faculty of Physics of Kiev State University in 1959 and stayed at the Department of Optics as a senior laboratory assistant. In 1962, he was appointed a senior research worker. In the following year, he was invited to the Chair of Optics at the University of Chernovitsy, where he took the position of Assistant Professor. In 1959, Vladislav Borisovich began active studies on the optical properties of semiconductors, with a particular emphasis on the examination of exciton±phonon spectra of cuprous oxide and phenomena related to spatial dispersion in the exciton region. The results obtained were acknowledged by the scientific community and underlay the Candidate's degree thesis, ``Quasiline absorption spectra of inorganic crystals'', which he defended in 1964. Beginning in 1966, V B Timofeev carried out some investigations concerned with the methods of precision spectrum interferential measurements and with holography, where he proposed methods of reference-free holographing. In 1967, V B Timofeev was invited to work as a Senior Researcher at the newly founded Institute of Solid State Physics (ISSP) RAS in Chernogolovka, not far from Moscow, which in due course became one of the leading research centers in Russia. V B Timofeev's entire further scientific activity and career are inseparably linked with ISSP RAS. At ISSP RAS, V B Timofeev has intensely and successfully developed a new direction related to the study of collective interactions in a system of nonequilibrium carriers and high-density excitons in semiconductors. V B Timofeev carried out research into nonequilibrium high-density electron±hole systems in direct band semiconductors (cadmium sulfide) and in semiconductors with an indirect forbidden band (germanium, silicon), in which he discovered basically new phenomena, namely, the exciton condensation to an electron±hole liquid in a polar direct-band semiconductor, a giant jump in photoconductivity under exciton metallization (Mott transition) in germanium, and exciton molecules in strained germanium and silicon crystals. He realized experimentally a new quantum objectÐa spin-oriented exciton gasÐand examined its quantum statistical properties at high densities. V B Timofeev comprehensively analyzed gas±liquid phase diagrams under exciton dielectric gas condensation to a metallic electron±hole liquid and, thus, laid the basis of the thermodynamics of nonequilibrium electron±hole systems. He revealed the giant probabilities of radiative recombination of exciton±impurity complexes in direct band semiconductors, as well as the phenomenon of their decay induced by the emission of acoustic phonons. V B Timofeev became a recognized leader in this new area in semiconductor physics. Part of the results of these studies was included in hisDoctor's degree thesis, ``Recombination emission of high-density excitons and nonequilibrium carriers'', successfully defended in 1975. V B Timofeev has often acutely changed the directions of his studies and has always achieved success. For instance, he was the first in the field of optical spectroscopy of hightemperature superconductors who carried out the study of inelastic light scattering attendant to the overgap excitations in oxide superconductors and revealed a strong scattering anisotropy resulting from the anisotropy of the superconducting gap. In the late 1980s, the scientific interests of V B Timofeev moved towards low-dimensional electron± hole and exciton systems in semiconductor heterostructures. Here, he discovered the effects of fractional quantization of Uspekhi Fizicheskikh Nauk 186 (9) 1027 ± 1028 (2016) DOI: 10.3367/UFNr.2016.08.037885 Translated by M V Tsaplina PERSONALIA PACS number: 01.60.+q

Kinetics of redox reactions and the variations of real charge-carrier concentrations across the SOFC electrode / electrolyte interfaces have critical importance for the fuel cell performance. The microscopic mechanisms of electrochemical processes in the vicinity of triple-phase boundary (TPB) can be assessed employing impedance spectroscopy, current-voltage measurements and various pulse techniques. Except for the micro-electrode approaches, however, these methods are cumulative. Moreover, unambiguous interpretation of the electrochemical measurement results requires, as a rule, to introduce complimentary experimental methods and/or to use simplified models. The present work is centered on the developments of a new combined technique for in-situ Raman spectroscopy studies of local chemical and electrochemical reactions, phase transitions, strains and morphological alterations in the SOFC electrodes under working conditions. The Raman spectroscopy was already successfully used to investigate both cathodic [1,2] and anodic [3] processes in SOFC, but the resultant information was mainly related to outer boundaries of the model electrochemical cells, primarily electrode surface, due to low penetration depth of the excitation radiation. The most important zones of the electrode systems, where the electrochemical reactions occur and ionic charge carriers are generated, cannot be achieved viewing the surface and edge areas. In the present work, this problem was solved by employing optically transparent, single-crystal membranes made of 10 mol.% Sc2O3 and 1% mol.% Y2O3 stabilized zirconia (10Sc1YSZ). In order to provide simultaneous Raman and electrochemical measurements of the cell placed under an oxygen chemical potential gradient, such as air/H2, a special controlled-atmosphere chamber was elaborated and tested. An appropriate selection of the electrodes geometry makes it possible to directly collect Raman spectra from the TPB zone, passing the beam through single-crystal solid electrolyte onto the interface, as a function of temperature, atmosphere, current density and/or overpotential. The results of case studies focused on redox kinetics of Ni-containing cermet anodes, are presented. This work was supported by grant 14-29-04031 of Russian Foundation for Basic Research. References S. Loridant, L. Abello, E. Siebert, G. Lucazeau, Solid State Ion. 78 (1995) 249-258 K. Blinn, H. Abernathy, M.Liu, Advances in Solid Oxide Fuel Cells V. (2010) 63-73 W. Bessler, M.Vogler, H. Stoermer, D. Gerthsen, A. Utz, A. Weber, E. Ivers-Tiffee, Phys. Chem. Chem. Phys., 12 (2010) 13888-13903