Expand this Topic clickable element to expand a topic
Skip to content
Optica Publishing Group

Simulation of enhanced backscattering of light by numerically solving Maxwell’s equations without heuristic approximations

Open Access Open Access

Abstract

We report what we believe to be the first simulation of enhanced backscattering (EBS) of light by numerically solving Maxwell’s equations without heuristic approximations. Our simulation employs the pseudospectral time-domain (PSTD) technique, which we have previously shown enables essentially exact numerical solutions of Maxwell’s equations for light scattering by millimeter-volume random media consisting of micrometer-scale inhomogeneities. We show calculations of EBS peaks of random media in the presence of speckle; in addition, we demonstrate speckle reduction using a frequency-averaging technique. More generally, this new technique is sufficiently robust to permit the study of EBS phenomena for random media of arbitrary geometry not amenable to simulation by other approaches, especially with regard to extension to full-vector electrodynamics in three dimensions.

©2005 Optical Society of America

Full Article  |  PDF Article
More Like This
Exact solution of Maxwell’s equations for optical interactions with a macroscopic random medium

Snow H. Tseng, Jethro H. Greene, Allen Taflove, Duncan Maitland, Vadim Backman, and Joseph T. Walsh
Opt. Lett. 29(12) 1393-1395 (2004)

Investigation of the noise-like structures of the total scattering cross-section of random media

Snow H. Tseng, Allen Taflove, Duncan Maitland, Vadim Backman, and Joseph T. Walsh
Opt. Express 13(16) 6127-6132 (2005)

Cited By

Optica participates in Crossref's Cited-By Linking service. Citing articles from Optica Publishing Group journals and other participating publishers are listed here.

Alert me when this article is cited.


Figures (3)

Fig. 1.
Fig. 1. PSTD simulation of the enhanced backscattering (EBS) numerical experiment. With dimensions of 800×400 µm, the rectangular cluster consists of N randomly positioned, non-contacting, infinitely long, dielectric cylinders with refractive index n=1.25; Each cylinder had a diameter of 1.2 µm with an average spacing of s=2.8 µm between cylinders (edge to edge). The rectangular cluster is illuminated by a coherent plane wave that is incident at 15° relative to the normal. Both the incident light and the backscattered light are polarized perpendicular to the plane of incidence, equivalent to collinear detection in EBS experiments. A standard anisotropic perfectly matched layer (APML) absorbing boundary condition is implemented to absorb outgoing waves, simulating a light scattering experiment in free space.
Fig. 2.
Fig. 2. PSTD-computed enhanced backscattered light (EBS) as a function of backscattering angle. 0° corresponds to direct backscattering at 15° from the normal. (a) Two examples of scattered light intensities, corresponding to two different rectangular clusters each consisting of N=10,000 cylinders, as shown in Fig. 1. (b) Ensemble average of 40 different rectangular clusters, showing a significant amount of speckle that partially obscures the EBS peak. (c) After averaging over 50 closely spaced frequencies, the speckle is significantly reduced and the EBS peak can be clearly seen.
Fig. 3.
Fig. 3. Comparison of PSTD-computed EBS peaks (solid lines) for three wavelengths with theoretical benchmark results (dash-dotted lines) for rectangular clusters consisting of N cylinders. (a)-(c) correspond to N=10,000 cylinders with ls ’=65.0 µm, 41.5 µm, and 37.7 µm, respectively; (d)-(e) correspond to N=20,000 cylinders with ls ’=32.5 µm, 20.7 µm, and 18.9 µm, respectively. The PSTD calculations are in good agreement with the benchmark theory.

Equations (2)

Equations on this page are rendered with MathJax. Learn more.

{ V x i } = F 1 ( j k ˜ x F { V i } )
α ( θ ) = 3 8 π [ 1 + 2 z 0 l + 1 ( 1 + q l ) 2 ( 1 + 1 exp ( 2 q z 0 ) q l ) ] * SF ( θ )
Select as filters


Select Topics Cancel
© Copyright 2024 | Optica Publishing Group. All rights reserved, including rights for text and data mining and training of artificial technologies or similar technologies.