The optimal form of the scanning near-field optical microscopy probe

A theoretical approach to determine the optimal form of the near-field optical microscope probe is proposed. An analytical expression of the optimal probe form with subwavelength aperture has been obtained. The advantages of the probe with the optimal form are illustrated using numerical calculations. The conducted calculations show 10 times greater light throughput and the reception possibility of the more compactly localized light at the output probe aperture which could indicate better spatial resolution of the optical images in near-field optical technique using optimal probe.Comment: 12 pages, 6 figure

Взаимосвязь промышленного и финансового стресса в российской экономике в условиях смены монетарного режима

The relevance of the paper is defined by significant impact of financial shocks on various sectors of the Russian economy, which undermines the stability of the country’s economic system. Therefore, it is essential to study the sources of financial shocks, the mechanisms of their distribution and ways to manage them. The purpose of the paper is to specify the impact of financial stress on industrial stress in the Russian economy and to determine the role of monetary policy in their interaction. The novelty of the research consists in the development of a methodology for constructing financial and industrial stress indices, the establishment of the mechanism of their interaction under different monetary regimes of the central bank. The construction of stress indices is carried out on the basis of the selected indicators of the financial market and industrial sector of the economy, the use of the principal component analysis for their aggregation, and mathematical transformation of the first principal component. The direction of interaction between financial and industrial stress in the Russian economy is determined using the Granger causality test. The construction of autoregressive distributed lag models (ARDL models) allows estimating the impact of financial stress, as well as monetary policy parameters (the scale of lending by the central bank to commercial banks and the deviation of the central bank’s key rate from the market rate borrowing) on industrial stress in the Russian economy. The research results in estimates of the strength of the relationship between financial and industrial stress in the Russian economy in two periods: before the change in the monetary regime (2006 — end of 2014) and after the change in the monetary regime (end of 2014–2019). It is concluded that in the first period the impact of financial stress on industrial stress was faster and stronger. In the second period, the weakening and distancing of this influence in time is explained by the change of the monetary regime of the Bank of Russia, which indicates an increase in the effectiveness of the monetary policy instruments of the Bank of Russia to counter “financial contagion” of the industrial sector.Актуальность исследования обусловлена существенным влиянием финансовых шоков на различные сектора российской экономики, что приводит к нарушению устойчивости экономической системы страны. Поэтому крайне важно знать источники финансовых шоков, механизмы их распространения и способы управления ими. Цель исследования — раскрытие особенностей влияния финансового стресса на промышленный стресс в российской экономике и определение роли денежно-кредитной политики в их взаимодействии. Новизна исследования заключается в развитии методологии построения индексов финансового и промышленного стресса, установлении механизма их взаимодействия в условиях разных монетарных режимов центрального банка. Построение индексов стресса осуществляется на основе отбора индикаторов финансового рынка и промышленного сектора экономики, использовании метода главных компонент для их агрегирования и математического преобразования первой главной компоненты. С помощью теста Грейнджера на причинность определяется направленность взаимодействия финансового и промышленного стресса в российской экономике. На основе построения моделей авторегрессии с распределенным лагом (ARDL моделей) выявляется характер и степень воздействия финансового стресса, а также параметров денежно-кредитной политики (масштабов кредитования центральным банком коммерческих банков и отклонения ключевой ставки центрального банка от рыночной ставки заимствования) на промышленный стресс в российской экономике. Результатом исследования являются оценки силы связи между финансовым и промышленным стрессом в российской экономике для двух периодов: до изменения монетарного режима (2006 — конец 2014 г.) и после изменения монетарного режима (конец 2014–2019 г). Сделан вывод, что в первом периоде влияние финансового стресса на промышленный стресс было более быстрым и сильным. Во втором периоде ослабление и отдаление этого влияния во времени объясняется сменой монетарного режима Банка России, что свидетельствует о повышении эффективности инструментов денежно-кредитной политики Банка России в противодействии «финансовому заражению» промышленного сектора экономики

Pulse area theorem in a single mode waveguide and its application to photon echo and optical memory in Tm3+:Y3Al5O12

We derive the area theorem for light pulses interacting with inhomogeneously broadened ensemble of two-level atoms in a single-mode optical waveguide and present its analytical solution for Gaussian-type modes, which demonstrates the significant difference from the formation of $2\pi$ pulses by plane waves. We generalize this theorem to the description of photon echo and apply it to the two-pulse (primary) echo and the revival of silenced echo (ROSE) protocol of photon echo quantum memory. For the first time, we implemented ROSE protocol in a single-mode laser-written waveguide made of an optically thin crystal $Tm^{3+}:Y_3Al_5O_{12}$. The experimental data obtained are satisfactorily explained by the developed theory. Finally, we discuss the obtained experimental results and possible applications of the derived pulse area approach

Scaling behaviour of relaxation dependencies in metaloxide superconductors

Superconducting glass state has been investigated in different types of metaloxide ceramics, Y-Ba-Cu-O, Bi-Sr-Ca-Cu-O, Ba-Pb-Bi-O, using the highly sensitive SQUID magnetometer. The analysis of long-time relaxation processes of thermoremanent magnetization m(sup trm) (+) = M(sub o) - Slnt displayed scaling dependence of the decay rate S = -dM/dlnt on quantity of trapped magnetic flux M(sub o): 1gs = 31g M(sub o) - observed universal dependence S is approximately M(sup 3) (sub o) seems to one of the features of superconducting glass state in metaloxide ceramics

Nephelometric Method for Determination of Growth Parameters of Chlorella Culture

Nephelometric method for the determination of growth parameters of chlorella culture using a photoelectric colorimeter was described. Use of photoelectric colorimeter for cell counting in suspension requires periodic calibration of meter readings using chlorella standard culture (with a certain cell concentration). Chlorella vulgaris IPPAS С-66, IPPAS С-111 and IPPAS С-2019 strains served as object of research. Density of initial in vitro suspensions (after inoculation) was 0.9 mln cells/ml. Cultivation was carried out during 12 days on a Hoagland medium with a pH of 7 (temperature of 35∘C, illumination of 10 klx). Sample selection for analysis and measurement was carried out daily, three times per day. Based on the obtained data, readings of photoelectric colorimeter KFK-3.01 were calibrated via direct count of chlorella cells quantity in Goryaev’s chamber. Use of calibration curve made it possible to reduce significantly time and error in determination of cell number in suspension cultures. The proposed technique allows counting chlorella cells in the growth and development dynamics with sufficient accuracy, high sensitivity, reproducibility and speed. It can be used for comparative determination of the growth parameters of strains in vitro, standardization of suspension cultures, semi-quantitative determination of chlorella biomass in order to predict the yield of desired product