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Andrey V. Tyukhtin - One of the best experts on this subject based on the ideXlab platform.

  • Electromagnetic field of a charge traveling into an Anisotropic Medium.
    Physical Review E, 2011
    Co-Authors: Sergey N. Galyamin, Andrey V. Tyukhtin
    Abstract:

    We analyze the electromagnetic field generated by a point charge intersecting the interface between vacuum and a nonmagnetic Anisotropic Medium with a plasma-type dispersion of the dielectric permittivity tensor. After penetrating the Medium, the charge moves along its main axis. The total field is presented as a sum of a self-field (i.e., a charge field in a corresponding unbounded Medium) and a scattered field associated with the boundary influence. We show that the self-field in the considered Anisotropic Medium is divided into a quasistatic field and a wave field (the so-called 'plasma trace' is absent in the case under consideration). Under certain conditions, the Vavilov-Cherenkov radiation generated in the Medium is reversed (i.e., the energy flux density vector forms an obtuse angle with the direction of the charge motion). Accordingly, so-called reversed Cherenkov-transition radiation (RCTR) can be generated. We analytically and numerically investigate both the scattered field and the total one, and we show that RCTR exists in the vacuum region if the charge velocity exceeds a certain threshold value associated with total internal reflection. Computations of the Fourier harmonics of the field as well as the total field itself demonstrate that RCTR in vacuum can be a dominant effect.more » Some properties of RCTR can be useful for diagnostics of particle bunches and determination of Medium characteristics.« less

  • Electromagnetic field of a charge traveling into an Anisotropic Medium
    Physical Review E - Statistical Nonlinear and Soft Matter Physics, 2011
    Co-Authors: Sergey N. Galyamin, Andrey V. Tyukhtin
    Abstract:

    We analyze the electromagnetic field generated by a point charge intersecting the interface between vacuum and a nonmagnetic Anisotropic Medium with a plasma-type dispersion of the dielectric permittivity tensor. After penetrating the Medium, the charge moves along its main axis. The total field is presented as a sum of a self-field (i.e., a charge field in a corresponding unbounded Medium) and a scattered field associated with the boundary influence. We show that the self-field in the considered Anisotropic Medium is divided into a quasistatic field and a wave field (the so-called "plasma trace" is absent in the case under consideration). Under certain conditions, the Vavilov-Cherenkov radiation generated in the Medium is reversed (i.e., the energy flux density vector forms an obtuse angle with the direction of the charge motion). Accordingly, so-called reversed Cherenkov-transition radiation (RCTR) can be generated. We analytically and numerically investigate both the scattered field and the total one, and we show that RCTR exists in the vacuum region if the charge velocity exceeds a certain threshold value associated with total internal reflection. Computations of the Fourier harmonics of the field as well as the total field itself demonstrate that RCTR in vacuum can be a dominant effect. Some properties of RCTR can be useful for diagnostics of particle bunches and determination of Medium characteristics.

Sergey N. Galyamin - One of the best experts on this subject based on the ideXlab platform.

  • Electromagnetic field of a charge traveling into an Anisotropic Medium.
    Physical Review E, 2011
    Co-Authors: Sergey N. Galyamin, Andrey V. Tyukhtin
    Abstract:

    We analyze the electromagnetic field generated by a point charge intersecting the interface between vacuum and a nonmagnetic Anisotropic Medium with a plasma-type dispersion of the dielectric permittivity tensor. After penetrating the Medium, the charge moves along its main axis. The total field is presented as a sum of a self-field (i.e., a charge field in a corresponding unbounded Medium) and a scattered field associated with the boundary influence. We show that the self-field in the considered Anisotropic Medium is divided into a quasistatic field and a wave field (the so-called 'plasma trace' is absent in the case under consideration). Under certain conditions, the Vavilov-Cherenkov radiation generated in the Medium is reversed (i.e., the energy flux density vector forms an obtuse angle with the direction of the charge motion). Accordingly, so-called reversed Cherenkov-transition radiation (RCTR) can be generated. We analytically and numerically investigate both the scattered field and the total one, and we show that RCTR exists in the vacuum region if the charge velocity exceeds a certain threshold value associated with total internal reflection. Computations of the Fourier harmonics of the field as well as the total field itself demonstrate that RCTR in vacuum can be a dominant effect.more » Some properties of RCTR can be useful for diagnostics of particle bunches and determination of Medium characteristics.« less

  • Electromagnetic field of a charge traveling into an Anisotropic Medium
    Physical Review E - Statistical Nonlinear and Soft Matter Physics, 2011
    Co-Authors: Sergey N. Galyamin, Andrey V. Tyukhtin
    Abstract:

    We analyze the electromagnetic field generated by a point charge intersecting the interface between vacuum and a nonmagnetic Anisotropic Medium with a plasma-type dispersion of the dielectric permittivity tensor. After penetrating the Medium, the charge moves along its main axis. The total field is presented as a sum of a self-field (i.e., a charge field in a corresponding unbounded Medium) and a scattered field associated with the boundary influence. We show that the self-field in the considered Anisotropic Medium is divided into a quasistatic field and a wave field (the so-called "plasma trace" is absent in the case under consideration). Under certain conditions, the Vavilov-Cherenkov radiation generated in the Medium is reversed (i.e., the energy flux density vector forms an obtuse angle with the direction of the charge motion). Accordingly, so-called reversed Cherenkov-transition radiation (RCTR) can be generated. We analytically and numerically investigate both the scattered field and the total one, and we show that RCTR exists in the vacuum region if the charge velocity exceeds a certain threshold value associated with total internal reflection. Computations of the Fourier harmonics of the field as well as the total field itself demonstrate that RCTR in vacuum can be a dominant effect. Some properties of RCTR can be useful for diagnostics of particle bunches and determination of Medium characteristics.

Hong Qing-quan - One of the best experts on this subject based on the ideXlab platform.

  • Radiation powers of magnetic dipole and electric quadrupole in magnetic Anisotropic Medium
    Acta Physica Sinica, 2010
    Co-Authors: Hong Qing-quan, Yu Yan-zhong, Cai Zhi-shan, Chen Mu-sheng, Lin Shun-da
    Abstract:

    Under the frame of classical electrodynamics, the electromagnetic radiation in magnetic Anisotropic Medium is investigated in this paper. The radiation power expressions for magnetic dipole and electronic quadrupole in magnetic Anisotropic Medium are in derived. Furthermore, the results, which are achieved by inserting the μ r in isotropic Medium into the obtained expressions, are agreed with the references. And the correctness of the obtained expressions is verified. The research results demonstrate that the radiation powers of magnetic dipole and electronic quadrupole are related to the μ r in magnetic Anisotropic Medium. This conclusion is very helpful for determining the radiation effects of magnetic dipole and electronic quadrupole in magnetic Anisotropic Medium.

  • Angle Distribution of Radiant Power of Electric Dipole in Anisotropic Medium
    Journal of Quanzhou Normal University, 2006
    Co-Authors: Hong Qing-quan
    Abstract:

    The article analyses angle distribution of radiant energy flow density and angle distribution of radiant power when an electric dipole is oscillating along polar axis in magnetic Anisotropic Medium,also compares them with the expression of that in isotropic Medium;thereby,a theoretical basis for more effectly using electric isotropic and magnetic Anisotropic Medium is obtained.

  • Total Radiant Power of Electric Dipole Radiation in Anisotropic Medium
    Journal of Quanzhou Normal University, 2004
    Co-Authors: Hong Qing-quan
    Abstract:

    With regard to the radiation of electromagnetic field in Anisotropic Medium,the (expression) of radiation field and powerflow density of electric dipole had been inferred.The total radiant power of electric dipole radiation in Anisotropic Medium is solved at Anisotropic coordinate system through surface integral at first;and then,an expression of total radiant power of electric dipole radiation in Anisotropic Medium formulating by ordinary rectangular coordinate system is obtained at isotropic coordinate system which is turned back from Anisotropic coordinate system after coordinate trans formation.When the Medium is isotropic,the results are identical with those of prediction.The correctness of inferred results is verified.The results not only can be applied to the judgement of the effect of radiation in Anisotropic Medium but also offer a theoretical basis for measuring total radiant power of electric dipole radiation in Anisotropic Medium and thus for seeking its development and application.

  • Energy flow density of magnetic dipole radiation in Anisotropic Medium
    Chinese Journal of Radio Science, 2004
    Co-Authors: Hong Qing-quan
    Abstract:

    Research on the problem of radiation in Anisotropic magnetic Medium, the author derives a general formula for radiation energy flow density of magnetic dipole radiation in Anisotropic Medium with tensor form.In orthogonal coordinate, the average energy flow density of magnetic dipole radiation in Anisotropic Medium is thereby obtained through switching agorithm. with regard to the direction of magnetic dipole radiation in Anisotropic Medium, a judgement is made on the direction of its concentration. A thereotical basis is thus offered for studying the development and the application of Anisotropic Medium. The formula deriving here is tested and verified finnally.

Li Lin - One of the best experts on this subject based on the ideXlab platform.

Liping Chang - One of the best experts on this subject based on the ideXlab platform.

  • correlation between intensity fluctuations of electromagnetic waves scattered from a spatially quasi homogeneous Anisotropic Medium
    Optics Express, 2016
    Co-Authors: Feinan Chen, Liping Chang
    Abstract:

    Within the validity of the first-order Born approximation, expressions are derived for the correlation between intensity fluctuations (CIF) of an electromagnetic plane wave scattered from a spatially quasi-homogeneous (QH), Anisotropic Medium. Upon establishing the correlation matrix of the scattering potential of the Medium, we show that the CIF is the summation of Fourier transforms of the strengths and normalized correlation coefficients (NCCs) of the scattering potential matrix. Numerical results reveal that the CIF is susceptible to the effective width and correlation length of the Medium, and degree of polarization of the incident electromagnetic wave. Our study not only extends the current knowledge of the CIF of a scattered field but also provides an important reference to the study of high-order intensity correlations of light scattered from a spatially Anisotropic Medium.

  • near field evanescent waves scattered from a spatially deterministic and Anisotropic Medium
    Optics Letters, 2015
    Co-Authors: Liping Chang
    Abstract:

    The scattering of light from an Anisotropic Medium, which may present either spatially random or deterministic statistics, has attracted substantial interest where the measurement of structural properties of scatterers is concerned. To date, however, no literature has studied near-zone evanescent waves scattered from a spatially deterministic and Anisotropic Medium. In this Letter, integral expressions are derived to represent electric fields of evanescent waves in the near-zone scattered field. In addition, the dependences of spectral densities of scattered field on the propagation distance of evanescent waves and effective radius of the scattering potential (ERSP) are also shown by numerical graphs, respectively. Potential applications of our study include the near-field optical microscopy and biomedical sensing.