Vestnik Moskovskogo Universiteta Seriya 3 Fizika Astronomiya最新文献_第3页

Suppression of local electron-phonon interaction in pi-conjugated oligomers and its monitoring using Raman scattering π共轭低聚物中局部电子-声子相互作用的抑制及其拉曼散射监测

Vestnik Moskovskogo Universiteta Seriya 3 Fizika Astronomiya Pub Date : 2023-09-20 DOI: 10.55959/msu0579-9392.78.2340404

A.Yu. Sosorev

{"title":"Suppression of local electron-phonon interaction in pi-conjugated oligomers and its monitoring using Raman scattering","authors":"A.Yu. Sosorev","doi":"10.55959/msu0579-9392.78.2340404","DOIUrl":"https://doi.org/10.55959/msu0579-9392.78.2340404","url":null,"abstract":"For efficient operation of many organic electronic devices, organic semiconductors with high charge carrier mobility are required. However, in most of the known organic semiconductors, the charge mobility is low, since it is limited by the strong local electron-phonon interaction. In the present work, using the example of thiophene-phenylene co-oligomers, a class of organic semiconductors that combine a sufficiently high charge mobility with light emission and therefore promising for light-emitting transistors and electrically pumped lasers, the mechanism of suppression of the electron-phonon interaction by introducing electronegative atoms or an additional thiophene ring is studied. It was found that such structural changes alter the contribution of various vibrational modes to the local electron-phonon interaction, in particular, to the suppression of the contribution of the low-frequency torsion mode. In addition, it is shown that for the two modes that make the largest contribution to the local electron-phonon interaction in an unsubstituted oligomer, this change correlates with their intensity of Raman scattering, and this confirms the promise of studying the electron-phonon interaction using Raman spectroscopy. The results obtained improve the understanding of the relationship between the local electron-phonon interaction and the molecular structure of organic semiconductors, which is extremely important for the directed design of such materials with high charge mobility.","PeriodicalId":484854,"journal":{"name":"Vestnik Moskovskogo Universiteta Seriya 3 Fizika Astronomiya","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136310742","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Test experiment to determine the time distribution of the background between MMF accelerator pulses on the RADEX channel 测试实验，以确定在RADEX通道上的MMF加速器脉冲之间的背景时间分布

Vestnik Moskovskogo Universiteta Seriya 3 Fizika Astronomiya Pub Date : 2023-09-20 DOI: 10.55959/msu0579-9392.78.2340203

M.V. Mordovskoy, A.A. Kasparov, V.V. Skorkin, I.V. Surkova

引用次数: 0

Optimization of near-field amplification at resonant light scattering by nanoparticles 纳米粒子共振光散射的近场放大优化

Vestnik Moskovskogo Universiteta Seriya 3 Fizika Astronomiya Pub Date : 2023-06-16 DOI: 10.55959/msu0579-9392.78.2330402

Trukhan E. A.

{"title":"Optimization of near-field amplification at resonant light scattering by nanoparticles","authors":"Trukhan E. A.","doi":"10.55959/msu0579-9392.78.2330402","DOIUrl":"https://doi.org/10.55959/msu0579-9392.78.2330402","url":null,"abstract":"In the present work, expressions for the system parameters that realize the maximum of the scattered field in the Mie problem separately for metals and for dielectrics were obtained. For metals, the answer was obtained in the form of formulas, for dielectrics an algorithm that allows finding the coordinates of the maximum is presented. The behavior of the solution, applied to real substances (Al, Au, GaP), is considered. In the case of the metals under relatively low dissipation at the resonant frequency, it accurately points to the maximum, and as the dissipation increases, it points to the neighborhood of the maximum. For considered dielectrics it was shown that theoretically predicted maximums are unattainable due to the limited value of the refractive index of the substance, the reasons why the maximums exist despite the mentioned limitation. In particular, it was found that the wavelength of the incident radiation and the radius of the particle at the maxima for GaP coincide with the resonance value for the internal coefficients. It was the starting point of the present study. Obtained results show that it really provides a guideline for searching for the maximum of the field scattered by other dielectrics spherical particles with a relatively low refractive index.","PeriodicalId":484854,"journal":{"name":"Vestnik Moskovskogo Universiteta Seriya 3 Fizika Astronomiya","volume":"76 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135622758","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Attosecond interferometry of neon atom: photoelectron angular distributions 氖原子的阿秒干涉测量:光电子角分布

Vestnik Moskovskogo Universiteta Seriya 3 Fizika Astronomiya Pub Date : 2023-06-16 DOI: 10.55959/msu0579-9392.78.2330401

Yudin S. N., Popova M. M., Gryzlova E. V., Kiselev M. D., Grum–Grzhimailo A. N.

引用次数: 0

Formation of hexagonal phase 9R-Si in SiO2/Si system upon Kr+ ion implantation Kr+离子注入后SiO2/Si体系中六方相9R-Si的形成

Vestnik Moskovskogo Universiteta Seriya 3 Fizika Astronomiya Pub Date : 2023-06-16 DOI: 10.55959/msu0579-9392.78.2330501

Nikolskaya A.A., Korolev D.S., Mikhaylov A.N., Konakov A.A., Okhapkin A.I., Kraev S.A., Andrianov A.I., Moiseev A.D., Sushkov A.A., Pavlov D.A., Tetelbaum D.I.

{"title":"Formation of hexagonal phase 9R-Si in SiO2/Si system upon Kr+ ion implantation","authors":"Nikolskaya A.A., Korolev D.S., Mikhaylov A.N., Konakov A.A., Okhapkin A.I., Kraev S.A., Andrianov A.I., Moiseev A.D., Sushkov A.A., Pavlov D.A., Tetelbaum D.I.","doi":"10.55959/msu0579-9392.78.2330501","DOIUrl":"https://doi.org/10.55959/msu0579-9392.78.2330501","url":null,"abstract":"Hexagonal silicon polytypes are attracting significant attention from the scientific community due to their potential applications in next-generation electronics and photonics. However, obtaining stable heterostructures based on both cubic and hexagonal polytypes is a complicated task. In the present work, the possibility of formation of hexagonal silicon of the 9R-Si phase using the traditional method of microelectronics, i.e. ion implantation, is shown. Implantation of Kr+ ions was carried out through a SiO2 layer, the thickness of which was approximately twice the projected range of Kr+ followed by high temperature annealing. High resolution transmission electron microscopy reveals that a thin amorphous layer forms in a Si substrate at the interface with the SiO2 film under implantation, upon recrystallization of which the formation of the 9R-Si polytype occurs during annealing. It is assumed that mechanical stresses are created during implantation through the oxide layer, that contributes to hexagonalization during high-temperature annealing. The dependence of the efficiency of hexagonalization on the substrate orientation is established. In addition to the formation of the 9R-Si phase, at the implantation and annealing parameters used, light-emitting defects are formed in silicon, the photoluminescence of which at a wavelength of ∼1240 nm is observed up to a temperature of ∼120 K. The obtained results can stimulate and expand the range of applications of ion-irradiated silicon in micro-, nano-, and optoelectronics","PeriodicalId":484854,"journal":{"name":"Vestnik Moskovskogo Universiteta Seriya 3 Fizika Astronomiya","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135622762","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Evaluation of the asteroid material composition by reflectance spectra using meteorite analogues 利用陨石类似物的反射光谱评价小行星的物质组成

Vestnik Moskovskogo Universiteta Seriya 3 Fizika Astronomiya Pub Date : 2023-06-16 DOI: 10.55959/msu0579-9392.78.2330801

Savelova A. A., Busarev V. V., Shcherbina M. P.

引用次数: 0

Nuclear ground state correlations 核基态相关

Vestnik Moskovskogo Universiteta Seriya 3 Fizika Astronomiya Pub Date : 2023-06-16 DOI: 10.55959/msu0579-9392.78.2330207

Kamerdzhiev S.P., Shitov M.I.

引用次数: 0

On the probable interpretation of anticorrelation between the proton temperature and density in the solar wind 太阳风中质子温度与密度反相关关系的可能解释

Vestnik Moskovskogo Universiteta Seriya 3 Fizika Astronomiya Pub Date : 2023-06-16 DOI: 10.55959/msu0579-9392.78.2330803

Dumin Yu.V., Lukashenko A.T., Svirskaya L.M.

{"title":"On the probable interpretation of anticorrelation between the proton temperature and density in the solar wind","authors":"Dumin Yu.V., Lukashenko A.T., Svirskaya L.M.","doi":"10.55959/msu0579-9392.78.2330803","DOIUrl":"https://doi.org/10.55959/msu0579-9392.78.2330803","url":null,"abstract":"The anticorrelated distributions of temperature and density of protons are a well-known property of the solar wind. Nevertheless, it is unclear till now if they are formed by some kind of the universal physical mechanism? Unfortunately, a straightforward comparison of the characteristic relaxation times for the temperature and density, on the one hand, and pressure, on the other hand, encounters the problem of inapplicability of the hydrodynamical approach in the situation when the free-path length of the protons is considerably greater than the spatial scale of the structures under consideration. To resolve this problem, some kinds of the MHD turbulence—reducing the effective free paths—are usually assumed. In the present paper, we use an alternative approach based on the electrostatic (Langmuir) turbulence, described by the mathematical formalism of the spin-type Hamiltonians, which was actively discussed in the recent time in the literature on statistical physics. As follows from the corresponding calculations, formation of the anticorrelated distributions of temperature and density is a universal property of the strongly nonequilibrium plasmas governed by the spintype Hamiltonians when they gradually approach the thermodynamic equilibrium. So, just this phenomenon could be responsible for the anticorrelations observed in the solar wind.","PeriodicalId":484854,"journal":{"name":"Vestnik Moskovskogo Universiteta Seriya 3 Fizika Astronomiya","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135622756","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Photoelectric charging of dust inprotoplanetary disks 原行星盘中尘埃的光电充电

Vestnik Moskovskogo Universiteta Seriya 3 Fizika Astronomiya Pub Date : 2023-06-16 DOI: 10.55959/msu0579-9392.78.2330802

Morozova T.I., Kuznetsov I.A.

引用次数: 0

Mutual changes in temperature and aerosol content in the atmosphere based on Antarctic ice core data for the last 800000 years 基于过去80万年南极冰芯资料的大气中温度和气溶胶含量的相互变化

Vestnik Moskovskogo Universiteta Seriya 3 Fizika Astronomiya Pub Date : 2023-06-16 DOI: 10.55959/msu0579-9392.78.2330903

Mokhov I.I.

{"title":"Mutual changes in temperature and aerosol content in the atmosphere based on Antarctic ice core data for the last 800000 years","authors":"Mokhov I.I.","doi":"10.55959/msu0579-9392.78.2330903","DOIUrl":"https://doi.org/10.55959/msu0579-9392.78.2330903","url":null,"abstract":"A comparative analysis of mutual changes in temperature and aerosol content in the atmosphere was carried out by the data of Antarctic ice cores obtained at the Russian Vostok station and within the framework of the international EPICA project for the past 800,000 years. According to the results of cross-wavelet analysis for the last hundreds of thousands of years, variations in the content of aerosol in the atmosphere, as well as in the content of greenhouse gases CO2 and CH4, are generally lagging relative to temperature changes for the glacial cycles that dominated within the past million years with periods of about 100 thousands years associated with change in the eccentricity of the Earth’s orbit around the Sun. At the same time, for shorter-term glacial cycles, opposite effects appear at certain time intervals with a delay in temperature variations relative to variations in the content of radiatively active components in the atmosphere, including marine and continental (dust) aerosol . In particular, the delay of temperature variations with respect to variations in the content of aerosol in the atmosphere (as well as with respect to variations in the content of methane in the atmosphere) manifests itself for modes associated with the obliquity changes with periods of about 40 thousands years.","PeriodicalId":484854,"journal":{"name":"Vestnik Moskovskogo Universiteta Seriya 3 Fizika Astronomiya","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135623019","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0