Internal Radiation Field in the Nonlinear Transfer Problem for a One-Dimensional Anisotropic Medium. II

Abstract Fourier integrals are set up for the field of a point charge moving uniformly in an arbitrary direction in a uniaxial medium anisotropic in ε only. The integrals break up into several parts two of which yield the ordinary and extraordinary cones with uniform azimuthal potential distribution. The remaining integrals neither contribute to the energy radiated nor affect the size and the shape of the cones, but merely distort the field within the cones. The integrals are evaluated exactly in the non-dispersive case and closed expressions for the potential are obtained. In the dispersive case, the radiation field is determined by using the asymptotic form of the Hankel functions occurring in the integrand. The resulting expressions exhibit the high azimuthal asymmetry characteristic of anisotropic fields. From the expressions derived for a pure dielectric the potential in a doubly anisotropic medium is obtained, without a fresh calculation, by making appropriate substitutions for the coordinates of the field point and the components of the dielectric tensor.

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Modified Unsplitted Perfectly Matched Layer Absorbing Boundary Conditions for Truncating Anisotropic Medium

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.900.386 ◽

2014 ◽

Vol 900 ◽

pp. 386-389

Author(s):

Zhi Chao Cai ◽

Li Xia Yang ◽

Hao Chuan Deng ◽

Xiao Wei ◽

Hong Cheng Yin

Keyword(s):

Boundary Conditions ◽

Anisotropic Medium ◽

Electromagnetic Wave Propagation ◽

Simulation Analysis ◽

Perfectly Matched Layer ◽

Absorbing Boundary Conditions ◽

Absorbing Boundary ◽

One Dimensional ◽

Derivatives Of ◽

Difference Time

To simulate Electromagnetic wave propagation in anisotropic media, absorbing boundary conditions are needed to truncate the computation domains. Based on the finite difference time domain method in anisotropic medium, the implementation of the modified nearly perfectly matched layer absorbing boundary conditions for truncating anisotropic medium is presented. By using the partial derivatives of space variables stretched-scheme in the coordinate system, the programming complexity is reduced greatly. According to one dimensional numerical simulation analysis, the modified nearly perfectly matched layer absorbing boundary condition is validated.

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Analytical solution of the simple nonlinear radiative transfer problem

Communications of the Byurakan Astrophysical Observatory ◽

10.52526/25792776-2018.2.2-364 ◽

2018 ◽

pp. 364-372

Author(s):

H. V. Pikichyan

Keyword(s):

Radiative Transfer ◽

Analytical Solution ◽

Transfer Problem ◽

Internal Field ◽

Field Problem ◽

Radiative Transfer Problem ◽

Absorbing Medium ◽

One Dimensional ◽

Radiation Beams ◽

Finite Optical Thickness

Exploring the "Principle of invariance" and the method of "Linear images", the simple nonlinear conservative problem of radiative transfer is analyzed. The solutions of nonlinear reection-transmission and internal field problems of one dimensional scattering-absorbing medium of finite optical thickness are obtained, whereas both boundaries of medium illuminated by powerful radiation beams. Using two different approaches - a direct and inverse problem, the analytical solution of the internal field problem is derived.

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