Персона:
Рогозкин, Дмитрий Борисович

Организационные подразделения

Организационная единица

Институт лазерных и плазменных технологий

Стратегическая цель Института ЛаПлаз – стать ведущей научной школой и ядром развития инноваций по лазерным, плазменным, радиационным и ускорительным технологиям, с уникальными образовательными программами, востребованными на российском и мировом рынке образовательных услуг.

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Трудовой контракт завершен

Фамилия

Рогозкин

Имя

Дмитрий Борисович

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Результаты поиска

Теперь показываю 1 - 10 из 18

Открытый доступ
Propagation and Depolarization of a Short Pulse of Light in Sea Water
(2020) Gorodnichev, E. E.; Kondratiev, K. A.; Kuzovlev, A. I.; Rogozkin, D. B.; Городничев, Евгений Евгеньевич; Кондратьев, Кирилл Александрович; Кузовлев, Александр Иванович; Рогозкин, Дмитрий Борисович
We present the results of a theoretical study of underwater pulse propagation. The vector radiative transfer equation (VRTE) underlies our calculations of the main characteristics of the scattered light field in the pulse. Under the assumption of highly forward scattering in seawater, three separate equations for the basic modes are derived from the exact VRTE. These three equations are further solved both within the small-angle approximation and numerically. The equation for the intensity is analyzed for a power-law parametrization of the wings of the sea water phase function. The distribution of early arrival photons in the pulse, including the peak intensity, is calculated. Simple relations are also presented for the variance of the angular distribution of radiation, the effective duration of the signal and other parameters of the pulse. For linearly and circularly polarized pulses, the temporal profile of the degree of polarization is calculated for actual data on the scattering matrix elements. The degree of polarization is shown to be described by the self-similar dependence on some combination of the transport scattering coefficient, the temporal delay and the source-receiver distance. Our results are in agreement with experimental and Monte-Carlo simulation data. The conclusions of the paper offer a theoretical groundwork for application to underwater imaging, communication and remote sensing.
Открытый доступ
Coherent backscattering from an ensemble of Mie-particles immersed in a magneto-active medium
(2020) Gorodnichev, E. E.; Rogozkin, D. B.; Городничев, Евгений Евгеньевич; Рогозкин, Дмитрий Борисович
© Published under licence by IOP Publishing Ltd.We show that coherent backscattering of light from a disordered sample in a magnetic field can exhibit unusual features. The helicity retention in scattering from particles of the sample underlies these features. In the magnetic field parallel to the sample surface, the peak of coherent backscattering of circularly polarized light shifts from the backward direction by an angle proportional to the magnetic field strength. For linearly polarized light the coherent backscattering cone splits into two ones. The results obtained correlate well with the available experimental data.
Только метаданные
Photon Doppler Velocimetry and Simulation of Ejection of Particles from the Surface of Shock-Loaded Samples
(2020) Andriyash, A. V.; Dyachkov, S. A.; Zhakhovsky, V. V.; Kalashnikov, D. A.; Rogozkin, D. B.; Рогозкин, Дмитрий Борисович
© 2020, Pleiades Publishing, Inc.Abstract: The results of photon Doppler velocimetry of ejecta from shock-loaded metal samples are reported. The experiments have been performed with tin and lead samples of a given thickness and a given surface roughness. The direct numerical simulation of the process of mass ejection from the surface of shock-loaded samples is performed for conditions close to experimental by the smoothed particle hydrodynamics method. The areal density and initial velocity distribution of the volume density of ejecta are determined. Using these results, we calculate the time dependence of the profile of the volume density at the expansion of the formed dust cloud to air. Applying an approach based on the transport equation for the correlation function of the scattered field, the main parameters of the velocity distribution of ejecta, areal density of ejecta, etc. are reconstructed from spectral photon Doppler velocimetry data. The experimentally observed temporal dynamics of spectra, which is caused by the drag of dust in air, is described at an appropriately chosen size dispersion of dust particles. The masses of ejecta reconstructed from experimental data are in agreement with the smoothed particle hydrodynamics results.
Только метаданные
Symmetry-induced enhancement of transmission through a disordered system
(2025) Flegontov, A. O.; Rogozkin, D. B.; Рогозкин, Дмитрий Борисович
Только метаданные
Modeling the Doppler spectrum of waves backscattered from an expanding cloud for anisotropic phase functions
(2024) Kondratev, A. N.; Andriyash, A. V.; Kuratov, S. E.; Rogozkin, D. B.; Рогозкин, Дмитрий Борисович
Только метаданные
Enhancement of mesoscopic fluctuations in transmission of light through a disordered medium at grazing angles
(2021) Sheberstov, S. V.; Kondrat'ev, K. A.; Marinyuk, V. V.; Rogozkin, D. B.; Кондратьев, Кирилл Александрович; Маринюк, Виталий Владиславович; Рогозкин, Дмитрий Борисович
© 2021 American Physical Society.We study how intensity fluctuations in transmission through a disordered slab change depending on the regime of wave transport. A system with large (compared to the wavelength of light) inhomogeneities is considered. Within a diagrammatic approach, the variance of the total transmission coefficient is calculated numerically beyond the diffusion approximation. A great enhancement of fluctuations is found in the crossover from the ballistic to the diffusive transport at the grazing angles of incidence on the sample surface. The effect originates from the reflection of waves that propagate nearly parallel to the sample boundaries and experience scattering through small angles, and reveals itself both in transmission and reflection and in correlations between the transmitted and reflected fluxes.
Только метаданные
Application of multiple scattering theory to Doppler velocimetry of ejecta from shock-loaded samples
(2020) Kondrat'ev, A. N.; Andriyash, A. V.; Kuratov, S. E.; Rogozkin, D. B.; Рогозкин, Дмитрий Борисович
© 2020 Elsevier LtdWe address the actual problem of retrieving the physical parameters of ejecta from data of heterodyne Doppler velocimetry. Under the assumption that ejected particles are randomly spaced and their number within the probed volume is great, the noise-free component of the power spectrum of heterodyne beats is shown to be expressed in terms of a solution to the transport equation for the field correlation function which accounts for multiple scattering and absorption of the probing beam in the ejecta cloud. This provides a means for theoretical modeling of experimental Doppler data. The ejecta cloud is considered as a plane layer of particles moving in the air away from the free-surface of the shock-loaded sample. The spatial profile of the scattering coefficient and the cloud thickness are related directly to the distribution of ejected particles over velocities and coordinates. The slowing-down of ejected particles in the air leads to an ambiguous relation between the velocity of particles and their position, resulting in essential complication of the particle distribution. Using a multi-group description of the ejecta cloud, we reduce the transport equation to a system of linked Milne-like equations. The system is solved numerically with the discrete ordinate code. Varying the values of the cloud optical thickness and the parameters of the particle distribution over sizes and initial velocities, we fit the calculated spectrum to the time-resolved data of heterodyne Doppler measurements. Such an approach enables retrieving the primary ejecta characteristics (the total ejected mass, the density-velocity profile and the size distribution of ejected particles) directly from heterodyne experiments. Application of the proposed method to the velocimetry data on ejecta is presented.
Только метаданные
Characterization of the aerosol contribution to the top-of-atmosphere radiance for satellite ocean color retrievals
(2024) Marinyuk, V. V.; Pavlova, M. A.; Rogozkin, D. B.; Sheberstov, S. V.; Маринюк, Виталий Владиславович; Рогозкин, Дмитрий Борисович
Открытый доступ
Diffusion of light through a disordered ensemble of resonant Mie-particles embedded in a medium with circular dichroism
(2019) Gorodnichev, E. E.; Rogozkin, D. B.; Городничев, Евгений Евгеньевич; Рогозкин, Дмитрий Борисович
© Published under licence by IOP Publishing Ltd.We study transmission of unpolarized light (incoherent superposition of right-hand circular and left-hand circular polarized waves) through an optically active medium doped by scattering Mie-particles. The medium is assumed to possess circular dichroism. Within the spatial diffusion approximation, the degree of circular polarization of the transmitted radiation is calculated. It is shown, that in the presence of scatterers a significant increase in the circular polarization compared to the medium with no scatterers can be observed.
Только метаданные
Circular dichroism in the presence of resonant Mie scatterers
(2019) Gorodnichev, E. E.; Rogozkin, D. B.; Городничев, Евгений Евгеньевич; Рогозкин, Дмитрий Борисович
Unpolarised light propagation is considered in a circularly dichroic medium with optically isotropic Mie-particles. The degree of passed radiation polarisation is calculated under the assumption that multiple scattering in such a system occurs in the spatial diffusion regime. It is shown that introducing Mie particles into a homogeneous sample with natural optical activity can noticeably enhance the observed circular dichroism, namely, increase a difference between the intensities of right- and left-handed polarised light passed through the medium. If the first Kerker condition is fulfilled for Mie particles, then the effect can be almost ten times stronger as compared to the case of a homogeneous sample.