162 research outputs found
Superconducting Single-photon Detectors Made of Ultra-thin VN Films
We optimized technology of thin VN films deposition in order to study VN-based superconducting single-photon detectors. Investigation of the main VN film parameters showed that this material has lower resistivity compared to commonly used NbN. Fabricated from obtained films devices showed 100% intrinsic detection efficiency at 900 nm, at the temperature of 1.7 K starting with the bias current of 0.7Β·
Intermediate result of negative consequences of the epidemic of the new coronavirus infection for the global economy
The epidemic of the new SARS-CoV-2 coronavirus infection slowed global economic growth and became the main threat for the global economy and financial markets in 2020. Authorities in many countries around the world have declared a health emergency. Without the experience of state quarantine, countries have faced negative consequences for citizens, the economy and financial market participants. The introduction of temporary regulatory easing in the context of the spread of a new coronavirus infection assisted to partially limit the negative consequences. The next few months will, probably, have a particularly strong impact on small business, as government support schemes are reduced or ceased. The article reveals the main consequences of the new coronavirus infection for the global economy
Spin pumping in YIG-Pt structures: the role of the van Hove singularities
Spin pumping by surface and backward volume magnetostatic waves in YIG/Pt
structures is experimentally studied and analyzed. It is shown that at
frequencies corresponding to van Hove singularities in the density of states of
the spin wave spectrum, an increase in the efficiency of electron-magnon
scattering and spin current generation takes place. The obtained results are
important for spin wave-based spintronic devices development
Communicative competence of a cardiologist: ethical and psychological analysis
The article problematizes the issue behind the standard categories of psychosocial factors, informing a patient about disease, prognosis, treatment methods, etc. The issue of a doctorβs role in interaction with a patient. Although psychological research methods are actively used in cardiology practice, and their results are quite transparent and demonstrate the specifics of patients experiencing the disease, affective states, soping skills, there are still questions about a physician not as a biomedical expert, but as a helping specialist. And although deontological imperatives require quite clear personal qualities from a doctor, the very realization of these qualities should be based on psychological approaches and culturalpsychological categories. As such, the way a doctor interacts with a patient can be described in terms of virtue ethics, which is an integral category that describes personal characteristics. Such characteristics, being implemented directly in clinical communication, could become a universal βrecipeβ for meaningful cooperation
Π Π΅Π·ΡΠ»ΡΡΠ°ΡΡ ΠΎΡΠ΅Π½ΠΊΠΈ ΡΡΠΈΠ±ΠΎΠ»ΠΎΠ³ΠΈΡΠ΅ΡΠΊΠΈΡ ΡΠ²ΠΎΠΉΡΡΠ² Π°Π²ΠΈΠ°ΡΠΈΠΎΠ½Π½ΡΡ ΠΌΠ°ΡΠ΅Π» Π΄Π»Ρ Π΄Π²ΠΈΠ³Π°ΡΠ΅Π»Π΅ΠΉ Π²ΠΎΠ·Π΄ΡΡΠ½ΡΡ ΡΡΠ΄ΠΎΠ²
The development of modern heat-stressed aircraft engines is a complex process based on the advanced achievements of various branches of science and technology, including chemmotology. Each new generation of aircraft engines imposes stricter requirements on the quality of the aviation oils used to ensure the reliable operation, including engine oil systems, rotor bearings and other components. One of the important factors in reducing friction and wear-out of modern gas turbine engines is the use of high-quality oils with a high level of anti-wear and anti-friction properties which allow engines to operate under various relubrication intervals. In the domestic regulatory and technical documentation, the anti-wear properties of aviation oils are evaluated using a four-ball friction machine according to GOST 9490, and the anti-friction properties are not taken into account. The specified friction machine has a variety of disadvantages. In this regard, the authors evaluated the anti-wear and anti-friction properties of domestic aviation oils using a versatile vibro-tribometer which allows for the operational properties of oils to be researched under the modes that are the most characteristic for the actual operation of aircraft engines compared with parameters of oil tests by a four-ball friction machine. Unlike the four-ball friction machine, the vibro-tribometer design implements a contact - interaction scheme in a βball-plate planeβ friction pair. At the same time, a thermal chamber is installed on this application that provides constant heating of the friction pair and the tested lubricating oils to the required temperature (from 0 to 150 β). It has been found that IPM-10 aviation oil possesses the best anti-wear and anti-friction properties, and with an increase in the tested oil temperature, a proportional increase in wear-out in the βball-plate planeβ friction pair occurs.Π Π°Π·ΡΠ°Π±ΠΎΡΠΊΠ° ΡΠΎΠ²ΡΠ΅ΠΌΠ΅Π½Π½ΡΡ
ΠΈ ΡΠ΅ΠΏΠ»ΠΎΠ½Π°ΠΏΡΡΠΆΠ΅Π½Π½ΡΡ
Π°Π²ΠΈΠ°ΡΠΈΠΎΠ½Π½ΡΡ
Π΄Π²ΠΈΠ³Π°ΡΠ΅Π»Π΅ΠΉ ΡΠ²Π»ΡΠ΅ΡΡΡ ΠΊΠΎΠΌΠΏΠ»Π΅ΠΊΡΠ½ΡΠΌ ΠΏΡΠΎΡΠ΅ΡΡΠΎΠΌ, ΠΊΠΎΡΠΎΡΡΠΉ ΠΎΡΠ½ΠΎΠ²ΡΠ²Π°Π΅ΡΡΡ Π½Π° ΠΏΠ΅ΡΠ΅Π΄ΠΎΠ²ΡΡ
Π΄ΠΎΡΡΠΈΠΆΠ΅Π½ΠΈΡΡ
ΡΠ°Π·Π»ΠΈΡΠ½ΡΡ
ΠΎΡΡΠ°ΡΠ»Π΅ΠΉ Π½Π°ΡΠΊΠΈ ΠΈ ΡΠ΅Ρ
Π½ΠΈΠΊΠΈ, Π²ΠΊΠ»ΡΡΠ°Ρ Ρ
ΠΈΠΌΠΌΠΎΡΠΎΠ»ΠΎΠ³ΠΈΡ. ΠΠ°ΠΆΠ΄ΠΎΠ΅ Π½ΠΎΠ²ΠΎΠ΅ ΠΏΠΎΠΊΠΎΠ»Π΅Π½ΠΈΠ΅ Π°Π²ΠΈΠ°ΡΠΈΠΎΠ½Π½ΡΡ
Π΄Π²ΠΈΠ³Π°ΡΠ΅Π»Π΅ΠΉ ΠΏΡΠ΅Π΄ΡΡΠ²Π»ΡΠ΅Ρ Π±ΠΎΠ»Π΅Π΅ ΠΆΠ΅ΡΡΠΊΠΈΠ΅ ΡΡΠ΅Π±ΠΎΠ²Π°Π½ΠΈΡ ΠΊ ΠΊΠ°ΡΠ΅ΡΡΠ²Ρ ΠΏΡΠΈΠΌΠ΅Π½ΡΠ΅ΠΌΡΡ
Π°Π²ΠΈΠ°ΡΠΈΠΎΠ½Π½ΡΡ
ΠΌΠ°ΡΠ΅Π», ΡΡΠ΅Π±ΡΠ΅ΠΌΡΡ
Π΄Π»Ρ ΠΎΠ±Π΅ΡΠΏΠ΅ΡΠ΅Π½ΠΈΡ Π½Π°Π΄Π΅ΠΆΠ½ΠΎΠΉ ΡΠ°Π±ΠΎΡΡ Π² ΡΠΎΠΌ ΡΠΈΡΠ»Π΅ ΠΌΠ°ΡΠ»ΠΎΡΠΈΡΡΠ΅ΠΌ Π΄Π²ΠΈΠ³Π°ΡΠ΅Π»Π΅ΠΉ, ΠΏΠΎΠ΄ΡΠΈΠΏΠ½ΠΈΠΊΠΎΠ² ΠΎΠΏΠΎΡ ΡΠΎΡΠΎΡΠΎΠ² ΠΈ Π΄ΡΡΠ³ΠΈΡ
ΡΠ·Π»ΠΎΠ². ΠΠ΄Π½ΠΈΠΌ ΠΈΠ· Π²Π°ΠΆΠ½ΡΡ
ΡΠ°ΠΊΡΠΎΡΠΎΠ² ΡΠ½ΠΈΠΆΠ΅Π½ΠΈΡ ΡΡΠ΅Π½ΠΈΡ ΠΈ ΠΈΠ·Π½ΠΎΡΠ° ΡΠΎΠ²ΡΠ΅ΠΌΠ΅Π½Π½ΡΡ
Π³Π°Π·ΠΎΡΡΡΠ±ΠΈΠ½Π½ΡΡ
Π΄Π²ΠΈΠ³Π°ΡΠ΅Π»Π΅ΠΉ ΡΠ²Π»ΡΠ΅ΡΡΡ ΠΈΡΠΏΠΎΠ»ΡΠ·ΠΎΠ²Π°Π½ΠΈΠ΅ Π²ΡΡΠΎΠΊΠΎΠΊΠ°ΡΠ΅ΡΡΠ²Π΅Π½Π½ΡΡ
ΠΌΠ°ΡΠ΅Π» Ρ Π²ΡΡΠΎΠΊΠΈΠΌ ΡΡΠΎΠ²Π½Π΅ΠΌ ΠΏΡΠΎΡΠΈΠ²ΠΎΠΈΠ·Π½ΠΎΡΠ½ΡΡ
ΠΈ Π°Π½ΡΠΈΡΡΠΈΠΊΡΠΈΠΎΠ½Π½ΡΡ
ΡΠ²ΠΎΠΉΡΡΠ², ΠΏΠΎΠ·Π²ΠΎΠ»ΡΡΡΠΈΡ
ΠΎΠ±Π΅ΡΠΏΠ΅ΡΠΈΡΡ ΡΠ°Π±ΠΎΡΡ Π΄Π²ΠΈΠ³Π°ΡΠ΅Π»Π΅ΠΉ ΠΏΡΠΈ ΡΠ°Π·Π»ΠΈΡΠ½ΡΡ
ΡΠ΅ΠΆΠΈΠΌΠ°Ρ
ΡΠΌΠ°Π·ΠΊΠΈ. Π ΠΎΡΠ΅ΡΠ΅ΡΡΠ²Π΅Π½Π½ΠΎΠΉ Π½ΠΎΡΠΌΠ°ΡΠΈΠ²Π½ΠΎ-ΡΠ΅Ρ
Π½ΠΈΡΠ΅ΡΠΊΠΎΠΉ Π΄ΠΎΠΊΡΠΌΠ΅Π½ΡΠ°ΡΠΈΠΈ ΠΏΡΠΎΡΠΈΠ²ΠΎΠΈΠ·Π½ΠΎΡΠ½ΡΠ΅ ΡΠ²ΠΎΠΉΡΡΠ²Π° Π°Π²ΠΈΠ°ΡΠΈΠΎΠ½Π½ΡΡ
ΠΌΠ°ΡΠ΅Π» ΠΎΡΠ΅Π½ΠΈΠ²Π°ΡΡΡΡ Ρ ΠΏΠΎΠΌΠΎΡΡΡ ΡΠ΅ΡΡΡΠ΅Ρ
ΡΠ°ΡΠΈΠΊΠΎΠ²ΠΎΠΉ ΠΌΠ°ΡΠΈΠ½Ρ ΡΡΠ΅Π½ΠΈΡ (Π§ΠΠ’) ΠΏΠΎ ΠΠΠ‘Π’ 9490, Π° Π°Π½ΡΠΈΡΡΠΈΠΊΡΠΈΠΎΠ½Π½ΡΠ΅ ΡΠ²ΠΎΠΉΡΡΠ²Π° Π½Π΅ ΡΡΡΠ΅Π½Ρ. Π£ΠΊΠ°Π·Π°Π½Π½Π°Ρ ΠΌΠ°ΡΠΈΠ½Π° ΡΡΠ΅Π½ΠΈΡ ΠΈΠΌΠ΅Π΅Ρ ΡΡΠ΄ Π½Π΅Π΄ΠΎΡΡΠ°ΡΠΊΠΎΠ². Π ΡΡΠΎΠΉ ΡΠ²ΡΠ·ΠΈ Π°Π²ΡΠΎΡΠ°ΠΌΠΈ ΠΏΡΠΎΠ²Π΅Π΄Π΅Π½Π° ΠΎΡΠ΅Π½ΠΊΠ° ΠΏΡΠΎΡΠΈΠ²ΠΎΠΈΠ·Π½ΠΎΡΠ½ΡΡ
ΠΈ Π°Π½ΡΠΈΡΡΠΈΠΊΡΠΈΠΎΠ½Π½ΡΡ
ΡΠ²ΠΎΠΉΡΡΠ² ΠΎΡΠ΅ΡΠ΅ΡΡΠ²Π΅Π½Π½ΡΡ
Π°Π²ΠΈΠ°ΡΠΈΠΎΠ½Π½ΡΡ
ΠΌΠ°ΡΠ΅Π» Ρ ΠΏΠΎΠΌΠΎΡΡΡ ΡΠ½ΠΈΠ²Π΅ΡΡΠ°Π»ΡΠ½ΠΎΠ³ΠΎ Π²ΠΈΠ±ΡΠΎΡΡΠΈΠ±ΠΎΠΌΠ΅ΡΡΠ°, ΠΏΠΎΠ·Π²ΠΎΠ»ΡΡΡΠ΅Π³ΠΎ ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°ΡΡ ΡΠΊΡΠΏΠ»ΡΠ°ΡΠ°ΡΠΈΠΎΠ½Π½ΡΠ΅ ΡΠ²ΠΎΠΉΡΡΠ²Π° ΠΌΠ°ΡΠ΅Π» ΠΏΡΠΈ ΡΠ΅ΠΆΠΈΠΌΠ°Ρ
, Π½Π°ΠΈΠ±ΠΎΠ»Π΅Π΅ Ρ
Π°ΡΠ°ΠΊΡΠ΅ΡΠ½ΡΡ
Π΄Π»Ρ ΡΠ΅Π°Π»ΡΠ½ΠΎΠΉ ΡΠΊΡΠΏΠ»ΡΠ°ΡΠ°ΡΠΈΠΈ Π°Π²ΠΈΠ°ΡΠΈΠΎΠ½Π½ΡΡ
Π΄Π²ΠΈΠ³Π°ΡΠ΅Π»Π΅ΠΉ, ΠΏΠΎ ΡΡΠ°Π²Π½Π΅Π½ΠΈΡ Ρ ΠΏΠ°ΡΠ°ΠΌΠ΅ΡΡΠ°ΠΌΠΈ ΠΈΡΠΏΡΡΠ°Π½ΠΈΠΉ ΠΌΠ°ΡΠ΅Π» Π½Π° ΡΠ΅ΡΡΡΠ΅Ρ
ΡΠ°ΡΠΈΠΊΠΎΠ²ΠΎΠΉ ΠΌΠ°ΡΠΈΠ½ΠΎΠΉ ΡΡΠ΅Π½ΠΈΡ. Π ΠΎΡΠ»ΠΈΡΠΈΠ΅ ΠΎΡ Π§ΠΠ’ Π² ΠΊΠΎΠ½ΡΡΡΡΠΊΡΠΈΠΈ Π²ΠΈΠ±ΡΠΎΡΡΠΈΠ±ΠΎΠΌΠ΅ΡΡΠ° ΠΈΡΠΏΠΎΠ»ΡΠ·ΡΠ΅ΡΡΡ ΡΡ
Π΅ΠΌΠ° ΠΊΠΎΠ½ΡΠ°ΠΊΡΠ° Π² ΠΏΠ°ΡΠ΅ ΡΡΠ΅Π½ΠΈΡ Β«ΡΠ°ΡΠΈΠΊ β ΠΏΠ»ΠΎΡΠΊΠΎΡΡΡ ΠΏΠ»Π°ΡΡΠΈΠ½ΡΒ». ΠΡΠΈ ΡΡΠΎΠΌ Π½Π° ΡΠΊΠ°Π·Π°Π½Π½ΠΎΠΌ ΠΏΡΠΈΠ±ΠΎΡΠ΅ ΡΡΡΠ°Π½ΠΎΠ²Π»Π΅Π½Π° ΡΠ΅ΡΠΌΠΎΠΊΠ°ΠΌΠ΅ΡΠ°, ΠΊΠΎΡΠΎΡΠ°Ρ ΠΎΠ±Π΅ΡΠΏΠ΅ΡΠΈΠ²Π°Π΅Ρ ΠΏΠΎΡΡΠΎΡΠ½Π½ΡΠΉ Π½Π°Π³ΡΠ΅Π² ΠΏΠ°ΡΡ ΡΡΠ΅Π½ΠΈΡ ΠΈ ΠΈΡΠΏΡΡΡΠ΅ΠΌΡΡ
ΡΠΌΠ°Π·ΠΎΡΠ½ΡΡ
ΠΌΠ°ΡΠ΅Π» Π΄ΠΎ ΡΡΠ΅Π±ΡΠ΅ΠΌΠΎΠΉ ΡΠ΅ΠΌΠΏΠ΅ΡΠ°ΡΡΡΡ (ΠΎΡ 0 Π΄ΠΎ 150 ΒΊΠ‘). ΠΠΎ ΡΠ΅Π·ΡΠ»ΡΡΠ°ΡΠ°ΠΌ ΠΈΡΠΏΡΡΠ°Π½ΠΈΠΉ ΡΡΡΠ°Π½ΠΎΠ²Π»Π΅Π½ΠΎ, ΡΡΠΎ Π½Π°ΠΈΠ»ΡΡΡΠΈΠΌΠΈ ΠΏΡΠΎΡΠΈΠ²ΠΎΠΈΠ·Π½ΠΎΡΠ½ΡΠΌΠΈ ΠΈ Π°Π½ΡΠΈΡΡΠΈΠΊΡΠΈΠΎΠ½Π½ΡΠΌΠΈ ΡΠ²ΠΎΠΉΡΡΠ²Π°ΠΌΠΈ ΠΎΠ±Π»Π°Π΄Π°Π΅Ρ ΠΌΠ°ΡΠ»ΠΎ Π°Π²ΠΈΠ°ΡΠΈΠΎΠ½Π½ΠΎΠ΅ ΠΠΠ-10, Π° Ρ ΡΠ²Π΅Π»ΠΈΡΠ΅Π½ΠΈΠ΅ΠΌ ΡΠ΅ΠΌΠΏΠ΅ΡΠ°ΡΡΡΡ ΠΈΡΠΏΡΡΠ°Π½ΠΈΠΉ ΠΌΠ°ΡΠ΅Π» ΠΏΡΠΎΠΈΡΡ
ΠΎΠ΄ΠΈΡ ΠΏΡΠΎΠΏΠΎΡΡΠΈΠΎΠ½Π°Π»ΡΠ½ΠΎΠ΅ ΡΠ²Π΅Π»ΠΈΡΠ΅Π½ΠΈΠ΅ ΠΈΠ·Π½ΠΎΡΠ° Π² ΠΏΠ°ΡΠ΅ ΡΡΠ΅Π½ΠΈΡ Β«ΡΠ°ΡΠΈΠΊ β ΠΏΠ»ΠΎΡΠΊΠΎΡΡΡ ΠΏΠ»Π°ΡΡΠΈΠ½ΡΒ»
Superconducting nanowire photon number resolving detector at telecom wavelength
The optical-to-electrical conversion, which is the basis of optical
detectors, can be linear or nonlinear. When high sensitivities are needed
single-photon detectors (SPDs) are used, which operate in a strongly nonlinear
mode, their response being independent of the photon number. Nevertheless,
photon-number resolving (PNR) detectors are needed, particularly in quantum
optics, where n-photon states are routinely produced. In quantum communication,
the PNR functionality is key to many protocols for establishing, swapping and
measuring entanglement, and can be used to detect photon-number-splitting
attacks. A linear detector with single-photon sensitivity can also be used for
measuring a temporal waveform at extremely low light levels, e.g. in
long-distance optical communications, fluorescence spectroscopy, optical
time-domain reflectometry. We demonstrate here a PNR detector based on parallel
superconducting nanowires and capable of counting up to 4 photons at
telecommunication wavelengths, with ultralow dark count rate and high counting
frequency
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