25-08-2017, 09:32 PM
2004: Finite-Difference Time Domain Solution of Light Scattering by an Infinite Dielectric Column Immersed in an Absorbing Medium
ABSTRACT
The two-dimensional (2-D) finite-difference time domain (FDTD) method is applied to calculate light scattering and
absorption by an arbitrarily shaped infinite column embedded in an absorbing dielectric medium. A uniaxial perfectly matched
layer (UPML) absorbing boundary condition (ABC) is used to truncate the computational domain. The single-scattering
properties of the infinite column embedded in the absorbing medium, including scattering phase functions, extinction and
absorption efficiencies, are derived using an area integration of the internal field. An exact solution for light scattering and
absorption by a circular cylinder in an absorbing medium is used to examine the accuracy of the 2-D UPML FDTD code.With
use of a cell size of 1/120 incident wavelength in the FDTD calculations, the errors in the extinction and absorption efficiencies
and asymmetry factors from the 2-D UPML FDTD are generally smaller than approx .1%. The errors in the scattering phase
functions are typically smaller than approx .4%. Using the 2-D UPML FDTD technique, light scattering and absorption by
long noncircular columns embedded in absorbing media can be accurately solved.