Slow light with integrated gain and large pulse delay

We demonstrate slow and stored light in Rb vapor with a combination of desirable features: minimal loss and distortion of the pulse shape, and large fractional delay (> 10). This behavior is enabled by: (i) a group index that can be controllably varied during light pulse propagation; and (ii) controllable gain integrated into the medium to compensate for pulse loss. Any medium with the above two characteristics should be able to realize similarly high-performance slow light.Comment: 5 pages, 4 figures; abstract is shortened, some typo correcte

Comparison of 87Rb N-resonances for D1 and D2 transitions

We report an experimental comparison of three-photon-absorption resonances (known as "N-resonances") for the D_1 and D_2 optical transitions of thermal 87Rb vapor. We find that the D_2 N-resonance has better contrast, a broader linewidth, and a more symmetric lineshape than the D_1 N-resonance. Taken together, these factors imply superior performance for frequency standards operating on alkali D_2 N-resonances, in contrast to coherent population trapping (CPT) resonances for which the D_2 transition provides poorer frequency standard performance than the D_1 transition.Comment: 3 pages, 4 figure

Century-long Dynamics of Meadow Steppes in the Privolzhskaya Uplands

Information on the structure and dynamics of the zonal Central Russian meadow steppes is presented in terms of the example of the Privolzhskaya forest-steppe state nature reserve (Penza region, Russia). The cenotic diversity of the herbaceous vegetation of the reserve is represented by 91 associations, of which 48 referto steppes and 43 to steppe meadows. It has been revealed that the vegetation of the studied placer sites under the influence of an absolutely reserved regime undergoes mesophyticization and silvatization, which are more intensively manifested in the forest-steppe landscapes of the secondary moraine plains (areas of thePoperechenskaya steppe and Ostrovtsovskaya forest-steppe reserve) than in the eroded denudational plains of forest-steppe landscapes (areas of the Kuncherovskaya steppe and Ostrovtsovskaya forest-steppe reserves). The study of the dynamics of zonal meadow steppes in the Volga Uplands testifies to the inevitability of theirtransformation in modern climatic conditions into meadow, shrubby and even forest communities. Keywords: forest-steppe, meadow steppes, structure, dynamics, succession, reserve, geobotanical mapping, protection of steppe vegetatio

A novel absorption resonance for all-optical atomic clocks

We report an experimental study of an all-optical three-photon-absorption resonance (known as a "N-resonance") and discuss its potential application as an alternative to atomic clocks based on coherent population trapping (CPT). We present measurements of the N-resonance contrast, width and light-shift for the D1 line of 87Rb with varying buffer gases, and find good agreement with an analytical model of this novel resonance. The results suggest that N-resonances are promising for atomic clock applications.Comment: 4 pages, 6 figure

Coherent population trapping resonances with linearly polarized light for all-optical miniature atomic clocks

We present a joint theoretical and experimental characterization of the coherent population trapping (CPT) resonance excited on the D1 line of 87Rb atoms by bichromatic linearly polarized laser light. We observe high-contrast transmission resonances (up to 25%), which makes this excitation scheme promising for miniature all-optical atomic clock applications. We also demonstrate cancellation of the first-order light shift by proper choice of the frequencies and relative intensities of the two laser field components. Our theoretical predictions are in good agreement with the experimental results.Comment: 8 pages, 7 figure

ПСИХОЛОГО-ПЕДАГОГІЧНІ ОСОБЛИВОСТІ РОЗРОБКИ ДИСТАНЦІЙНОГО НАВЧАЛЬНОГО КУРСУ З ДИСЦИПЛІНИ «ПСИХОЛОГІЧНЕ КОНСУЛЬТУВАННЯ»

Розглянуто проблему психолого-педагогічного забезпечення організації матеріалів дистанційних навчальних курсів на прикладі розробленого авторського модуля до курсу «Психологічне консультування»

Forecast for the zone of viticulture in European Russia under climate change

Climate warming has turned out to be a significant factor in viticulture and winemaking in all grape-growing areas of the world. Many countries consider the advance of viticulture to the north and to mountainous areas as a possible way to adapt to warming. The factors limiting the zone of viticulture in Russia have been identified by Soviet scientist F.F. Davitaya in 1948, and they are still relevant. They are the sum of active temperatures above 10 °C (ΣT10 > 2500 °C), mean of absolute minimum temperatures (Tmin > –35 °C), length of the frost-free period (Lff < 150 days), and hydrothermal coefficient (0.5 < HTC < 2.5). The values of these limiting factors in the present-day zone of commercial viticulture (ZCV) correspond to the ranges defined by F.F. Davitaya, with the exception of Tmin, which in the modern ZCV in European Russia is above –26 °C everywhere. The objective of this work was to assess the possibility of moving the boundaries of the ZCV to the north under the existing and predicted climate conditions in European Russia. The 1980–2019 daily data from 150 weather stations of the Federal Service for Hydrometeorology and Environmental Monitoring were used to calculate mean long-term values, trends and forecasts for 2050 for the ZCV limiting factors and locate the points lying in the range acceptable for viticulture. The QGIS program was applied to plot the points on the European Russia map and mark the terminal latitude. Versions with Tmin > –26 °C and Tmin > –35 °C were considered. On average for European Russia, in 1980–2019, there was an increase in ΣT10, Tmin, and Lff and a decrease in HTC. However, in the same period, Tmin showed a tendency toward decreasing at a number of points at latitudes lower than 55° N. The increase in heat supply during the growing season in European Russia implies a possibility of expanding the ZCV northward, beyond the present-day terminal latitude of 46.6° N, to 51.8° N under the existing conditions, and up to 60.7° N by 2050. In addition, even under the current conditions viticulture is possible in the area of Kaliningrad (54° N, 20° E). Using extra protective measures in winters not colder than –35 °C would make it possible to grow grapes at up to 53.3° N under the current conditions and at up to 60.7° N under the prognosticated ones. At the same time, a possible decrease in the minimum winter temperature at the south of European Russia will require additional protective measures in winter, while an increase in the aridity of the climate on the northwest coast of the Caspian Sea will reduce the area under non-irrigated vineyards

Особа, яка підлягає кримінальній відповідальності за фінансування тероризму

Новікова, Л. В. Особа, яка підлягає кримінальній відповідальності за фінансування тероризму / Л. В. Новікова // Вісник Національного університету внутрішніх справ. - 2004. – Вип. 27. - С. 18-21Проаналізовано, що фінансування тероризму може здійснюватися безпосередньо фізичними особами, а також за допомогою застосування ними юридичних осіб та державних структур. При цьому кримінальній відповідальності повинна підлягати лише фізична особа. Юридична особа у зв’язку з вчиненим суб'єктом кримінальної відповідальності злочином може нести адміністративну, матеріальну, моральну відповідальність, а держава – міжнародно-правову відповідальність. Проанализировано, что финансирование терроризма может осуществляться непосредственно физическими лицами, а также с помощью применения ими юридических лиц и государственных структур. При этом уголовной ответственности должно подлежать только физическое лицо. Юридическое лицо в связи с совершенным субъектом уголовной ответственности преступлением может нести административную, материальную, моральную ответственность, а государство - международно-правовую ответственность. It is analyzed that the financing of terrorism can be carried out directly by individuals, as well as through the use of legal entities and government agencies. In this case, only an individual should be subject to criminal liability. A legal entity in connection with a crime committed by the subject of criminal liability may bear administrative, material, moral responsibility, and the state may bear international legal responsibility

Cancellation of light-shifts in an N-resonance clock

We demonstrate that first-order light-shifts can be cancelled for an all-optical, three-photon-absorption resonance ("N-resonance") on the D1 transition of Rb87. This light-shift cancellation enables improved frequency stability for an N-resonance clock. For example, using a table-top apparatus designed for N-resonance spectroscopy, we measured a short-term fractional frequency stability (Allan deviation) 1.5e-11 tau^(-1/2) for observation times 1s< tau < 50s. Further improvements in frequency stability should be possible with an apparatus designed as a dedicated N-resonance clock.Comment: 4 pages, 4 figure