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Diode laser spectroscopy investigation of filaments in microwave plasma in dense gas
P. 301-311.
Avetisov V. G., Gritsinin S. I., Khusnutdinov A. N., Kossyi I. A., Misakyan M. A., Nadezhdinskii A. I., Tarasova N. M.
The results of measurements of an electron density in a microwave plasma filament in dense gas (argon) are reported. The electron density has been determined on the basis of Stark broadening of lines detected in the absorption spectrum. A high-resolution spectrometer incorporating GaAlAs diode laser operating at 870 nm has been used to measure Stark broadening and shifts of the argon line. The electron density in the filament was found to increase from the initial level of 10 exp 12/cu cm to value n sub e greater than 10 exp 16/cu cm. The dependencies of the electron density on gas pressure and microwave power density are presented.
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English
Максимов М. В., Nadtochiy A., Zhukov A., , in : SPIE PHOTONICS EUROPE 2020 Biophotonics in Point-of-Care. Vol. 11361: Biophotonics in Point-of-Care.: Bellingham : SPIE, 2020. P. 1135601-1135607.
We report on broad-area lasers, mode-locked lasers (MLLs), and superluminescent light-emitting diodes (SLDs) based on a recently developed novel type of nanostructures that we refer to as quantum well-dots (QWDs). The QWDs are intermediate in properties between quantum wells and quantum dots and combine some useful properties of both. 1.08 μm InGaAs/GaAs QWDs broad area edge-emitting lasers based ...
Added: October 9, 2020
Zaitsev V. V., V. E. Shaposhnikov, Monthly Notices of the Royal Astronomical Society 2022 Vol. 513 No. 3 P. 4082-4089
On the example of the hot Jupiter HD 189733b, in whose magnetosphere the conditions for the ’operation’ of an electron–cyclotron maser are not fulfilled, an analysis of the plasma mechanism of radio emission generation is carried out. The purpose of the analysis is to highlight the range of parameters at which the realization of a ...
Added: January 26, 2023
Kalatskiy A. Y., Afanasiev A., Melentiev P. et al., Laser Physics 2017 Vol. 27 No. 5 P. 055703
In this work, we investigated the frequency stabilization method of a diode laser that operates on the excited state transition 5P→5D of Rb atoms. The described technique allows simple control of the diode laser frequency stabilization to be performed. The critial parameters of stabilization, such as laser intensity and the temperature of a reference cell, ...
Added: December 3, 2019
Shuvalov S. D., Shestakov A. Y., Nosov A. V. et al., Instruments and Experimental Techniques 2020 Vol. 63 No. 2 P. 238-242
An EKOS compact electronic spectrometer is described, which has been designed for simultaneous
(below, this means the simultaneous accumulation of electron counts with various parameters) registration
of solar wind electrons in a relatively wide energy range. Computer simulation of the electronic optics
scheme of the instrument made it possible to obtain the following analytical characteristics: a range of ...
Added: October 12, 2021
Vinnichenko M. Y., Makhov I., Ustimenko R. V. et al., , in : 2022 47th International Conference on Infrared, Millimeter and Terahertz Waves (IRMMW-THz). : IEEE, 2022. P. 1-2.
Added: October 25, 2022
Demenev A. A., Kulakovskii V.D., Schneider C. et al., Applied Physics Letters 2016 Vol. 109 No. 17 P. 171106-1-171106-4
We report close to circularly polarized lasing at 1.473 and 1.522 eV from an AlAs/ AlGaAs Bragg microcavity, with 12 GaAs quantum wells in the active region and chirally etched upper distributed Bragg refractor under optical pump at room temperature. The advantage of using the chiral photonic crystal with a large contrast of dielectric permittivities ...
Added: February 15, 2018
Boldyrev K., Маврин Б. Н., Шерин П. С. et al., Journal of Luminescence 2018 Vol. 193 P. 119-124
We report on the quantum yield (eta) and decay time (tau) measurements at room temperature for the bright red-orange (602 nm) luminescence from new germanium-vacancy (Ge-V) centers in nano- and microcrystalline diamonds synthesized at high pressure and high temperature. The values eta = 3 +/- 1% and tau = 6.2 +/- 0.2 ns were found. ...
Added: February 8, 2019
Omelchenko A., Zhukov A. E., Korenev V. V. et al., Semiconductors 2013 Vol. 47 No. 10 P. 1397-1407
It is analytically shown that the both the charge carrier dynamics in quantum dots and their capture into the quantum dots from the matrix material have a significant effect on two-state lasing phenomenon in quantum dot lasers. In particular, the consideration of desynchronization in electron and hole capture into quantum dots allows one to describe ...
Added: September 17, 2018
Bespalov P. A., Olga N. Savina, Monthly Notices of the Royal Astronomical Society 2020 Vol. 498 P. 2864-2870
A model for the source of microwave main giant pulses (GPs) from the Crab pulsar is proposed and partly investigated. Pulse excitation takes place in a relativistic pair plasma with a strong magnetic field through the beam pulse amplifier (BPA) mechanism, in which short noise pulses of a certain type are amplified by energetic electrons ...
Added: August 18, 2020
Khoroshutin A. V., Lypenko D. A., Korlyukov A. et al., Synthetic Metals 2022 Vol. 287 Article 117094
A series of tricyclic naphthothiophenes – photocyclization products (8-methoxynaphtho[1,2-b]thiophene; 6,7-dimethoxynaphtho[1,2-b]thiophene; 8-methoxynaphtho[2,1-b]thiophene) have been studied. HOMO and LUMO levels, as well as a gap between them was accessed by cyclic voltammetry and optical spectroscopy. Double potential step chronoamperometry showed that the former naphthothiophene exhibits slower current decay than the other substances. Charge carrier mobility measured by the CELIV technique was ...
Added: June 7, 2022
Zubov F. I., Shernyakov Y. M., Gordeev N. Y. et al., Quantum Electronics 2022 Vol. 52 No. 7 P. 593-596
Lasers of different designs (stripe lasers and lasers with a half-disk cavity) based on InGaAs quantum dots formed by a mechanism different from the Stransky – Krastanov growth are studied. The possibility of lasing on the fundamental optical transition at record-high (134 – 153 cm–1) optical losses is demonstrated. The saturated modal gain is estimated ...
Added: December 13, 2022
Petrukhin N., Ruderman M. S., Shurgalina E. G., Monthly Notices of the Royal Astronomical Society 2018 Vol. 474 No. 2 P. 2289-2301
We study damping of phase-mixed Alfvén waves propagating in non-reflective axisymmetric magnetic plasma configurations. We derive the general equation describing the attenuation of the Alfvén wave amplitude. Then we applied the general theory to a particular case with the exponentially divergent magnetic field lines. The condition that the configuration is non-reflective determines the variation of ...
Added: February 6, 2018
Novikov L., Voronina E. N., Chernik V. N. et al., Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 2017 Vol. 410 P. 60-67
This paper presents results of experimental investigation of combined impact of 500 keV protons with fluences of 1015–1016 cm−2 and oxygen plasma with fluences of (0.8–3.5) 1020 cm−2 on polyimide films. Measured UV–vis transmission, Raman and XPS spectra of polyimide specimens before and after combined impact and data on the sample mass losses as a result of erosion due ...
Added: January 19, 2018
Omelchenko A., Zhukov A. E., Korenev V. V. et al., Journal of Physics: Conference Series 2014 Vol. 572 P. 012034
It is shown in analytical form that the carrier capture from the matrix as well as carrier dynamics in quantum dots plays an important role in double-state lasing phenomenon. In particular, the de-synchronization of hole and electron captures allows one to describe recently observed quenching of ground-state lasing, which takes place in quantum dot lasers ...
Added: September 17, 2018
Kascheev N. I., Kozyrev O., Leykin M. et al., , in : Proceedings of XV IEEE East-West Design & Test Symposium (EWDTS'2017). : Piscataway : IEEE, 2017. P. 1-4.
The secular outcome of our investigation is development of new monitoring service for glucose control related to diabetes. It is based on the main results of research: 1) New innovative wearable sensor that carry non-invasive measurement of glucose level. Sensor uses several independent technologies, simultaneously: radio-frequency with different levels of signal, ultrasonic, electromagnetic and thermal; ...
Added: February 20, 2018
Ruderman M.., Petrukhin N., Astronomy and Astrophysics 2017 Vol. 600 No. A122 P. 1-11
The ability of phase mixing to provide efficient damping of Alfvén waves even in weakly dissipative plasmas made it a popular mechanismforexplainingthesolarcoronalheating.Initiallyitwasstudiedintheequilibriumconfigurationswiththestraightmagnetic fieldlinesandtheAlfvénspeedonlyvaryinginthedirectionperpendiculartothemagneticfield.LatertheanalysisoftheAlfvénwave phase mixing was extended in various directions. In particular it was studied in two-dimensional planar magnetic plasma equilibria. Analytical investigation was carried out under the assumption that the wavelength is much smaller ...
Added: May 10, 2017
Kryzhanovskaya N., Moiseev E., Максимов М. В. et al., Bellingham : SPIE, 2020
Proceedings of the SPIE PHOTONICS EUROPE Conference on Biophotonics in Point-of-Care, 6-10 April 2020, Online Only, France. Proc. SPIE volume 11361 ...
Added: September 21, 2020
The BELLE C., Mizuk R., Aushev T. et al., Journal of High Energy Physics 2021 Vol. 2021 No. 6 Article 137
We report the first measurement of the exclusive cross sections e+e− → 𝐵𝐵⎯⎯⎯⎯BB¯, e+e− → 𝐵𝐵⎯⎯⎯⎯∗BB¯∗, and e+e− → 𝐵∗𝐵⎯⎯⎯⎯∗B∗B¯∗ in the energy range from 10.63 GeV to 11.02 GeV. The B mesons are fully reconstructed in a large number of hadronic final states and the three channels are identified using a beam-constrained-mass variable. The shapes of the exclusive cross sections show oscillatory behavior with several maxima ...
Added: December 16, 2021
Жуков А. Е., СПб. : ПОЛИТЕХ-ПРЕСС, 2019
Пособие включает в себя учебные материалы по физике и технологии полупроводниковых квантовых точек и лазеров на основе квантовых точек, включая микролазеры. Квантовые точки – это новая разновидность полупроводниковых квантоворазмерных структур (наноструктур), в которых движение носителей заряда ограничено во всех трех направлениях. Возникающая в результате размерного квантования модификация плотности состояний, а также большая энергия локализации носителей ...
Added: February 10, 2020
Matyushkin Y., Kaurova N., Voronov B. et al., Fullerenes Nanotubes and Carbon Nanostructures 2020 Vol. 28 No. 1 P. 50-53
We report an experimental study of the band structure of individual carbon nanotubes (SCNTs) based on investigation of the tunneling density of states, i.e. tunneling spectroscopy. A common approach to this task is to use a scanning tunneling microscope (STM). However, this approach has a number of drawbacks, to overcome which, we propose another method–tunneling ...
Added: October 29, 2020
Ruderman M., Petrukhin N., Astronomy and Astrophysics 2019 Vol. 631 P. A31-1-A31-12
ABSTRACT
The effect of siphon flow on kink oscillations of magnetic flux tubes is studied in the thin tube and thin boundary layer (TTTB) approximation. The presence of a transitional layer results in oscillation damping due to resonance absorption. To calculate the damping rate we use the regular perturbation method with the ratio of transitional layer ...
Added: October 17, 2019
Zaitsev V. V., Shaposhnikov V., Khadachenko M. L. et al., Geomagnetism and Aeronomy 2023 Vol. 63 No. 7 P. 892-898
On exoplanets with a weak magnetic field, the so-called plasma maser can be effectively implemented
instead of an electron cyclotron maser. This maser involves the generation of plasma waves by energetic
electrons and their conversion into radio emissions at the plasma frequency or at the double frequency.
Under specific conditions, a maser effect occurs at the plasma frequency, ...
Added: February 20, 2024
Vinnichenko M. Y., Makhov I., Kharin N. Y. et al., Semiconductors 2022 Vol. 55 No. 9 P. 710-716
The low-temperature impurity-assisted photoconductivity and absorption spectra of a nanostructure
with acceptor-doped multiple GaAs/AlGaAs quantum wells are investigated. The experimental absorption
and photoconductivity spectra agree well with each other. Using the calculated energy spectrum of the
hole and acceptor states in the quantum wells, the contributions of the transitions of holes from the ground
acceptor state to the delocalized ...
Added: March 14, 2022
Zhukova V., Mizuk R., Adachi I. et al., Journal of High Energy Physics 2023 Vol. 2023 Article 131
We report the first measurement of the inclusive e+e−→bb¯→D±sX and e+e−→bb¯→D0/D¯0X cross sections in the energy range from 10.63 to 11.02. Based on these results, we determine σ(e+e−→B0sB¯0sX) and σ(e+e−→BB¯X) in the same energy range. We measure the fraction of B0s events at Υ(10860) to be fs=(22.0+2.0−2.1)%. We determine also the ratio of the B0s inclusive branching fractions B(B0s→D0/D¯0X)/B(B0s→D±sX)=0.416±0.018±0.092. The results are obtained using the data collected with the Belle detector at the KEKB ...
Added: November 30, 2023