Related Experiment Video
Updated: May 27, 2026
11:34
Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
Coherent backscattering by polydisperse discrete random media: exact T-matrix results
Michael I Mishchenko1, Janna M Dlugach, Daniel W Mackowski
1NASA Goddard Institute for Space Studies, New York, New York 10025, USA. michael.i.mishchenko@nasa.gov
Optics Letters
|November 18, 2011
Summary
This study uses the T-matrix method to analyze electromagnetic scattering in particle mixtures. Findings confirm weak localization of light in random media, with polarization effects diminishing as particle size increases.
Area of Science:
- Electromagnetic theory
- Wave propagation
- Optical physics
Background:
- Electromagnetic scattering is fundamental to understanding light interaction with matter.
- Weak localization of electromagnetic waves describes interference phenomena in random media.
- Previous studies have explored these effects in various media.
Purpose of the Study:
- To compute electromagnetic scattering by finite spherical volumes of polydisperse particle mixtures.
- To investigate the manifestations of weak localization in discrete random media.
- To analyze the robustness of the polarization opposition effect in relation to particle size.
Main Methods:
- Utilizing the numerically exact superposition T-matrix method.
- Calculating far-field backscattering patterns from polydisperse multiparticle volumes.
- Analyzing scattering from mixtures with varying particle size parameters and refractive indices.
Main Results:
- Demonstrated classical manifestations of weak localization of electromagnetic waves.
- Corroborated the universal interference nature of coherent backscattering.
- Showed that the polarization opposition effect fades with increasing particle size parameter.
Conclusions:
- The T-matrix method accurately models electromagnetic scattering in complex media.
- Weak localization is a universal phenomenon in discrete random media.
- Particle size significantly influences the observability of polarization effects in weak localization.
Related Concept Videos
02:18Interference and Diffraction
Interference is a characteristic phenomenon exhibited by waves. When two electromagnetic waves interact with their peaks and troughs coinciding, a resulting wave with enhanced amplitude is produced. This is known as constructive interference. In this case, the two waves interacting are in phase with each other.
01:18First Law: Particles in Two-dimensional Equilibrium
Recall that a particle in equilibrium is one for which the external forces are balanced. Static equilibrium involves objects at rest, and dynamic equilibrium involves objects in motion without acceleration; but it is important to remember that these conditions are relative. For instance, an object may be at rest when viewed from one frame of reference, but that same object would appear to be in motion when viewed by someone moving at a constant velocity.
Newton's first law tells us about the...
Newton's first law tells us about the...
01:10First Law: Particles in One-dimensional Equilibrium
Newton's first law of motion states that a body at rest remains at rest, or if in motion, remains in motion at constant velocity, unless acted on by a net external force. It also states that there must be a cause for any change in velocity (a change in either magnitude or direction) to occur. This cause is a net external force. For example, consider what happens to an object sliding along a rough horizontal surface. The object quickly grinds to a halt, due to the net force of friction. If we...
01:28Symmetry in Maxwell's Equations
Once the fields have been calculated using Maxwell's four equations, the Lorentz force equation gives the force that the fields exert on a charged particle moving with a certain velocity. The Lorentz force equation combines the force of the electric field and of the magnetic field on the moving charge. Maxwell's equations and the Lorentz force law together encompass all the laws of electricity and magnetism. The symmetry that Maxwell introduced into his mathematical framework may not be...
00:59Propagation of Uncertainty from Random Error
An experiment often consists of more than a single step. In this case, measurements at each step give rise to uncertainty. Because the measurements occur in successive steps, the uncertainty in one step necessarily contributes to that in the subsequent step. As we perform statistical analysis on these types of experiments, we must learn to account for the propagation of uncertainty from one step to the next. The propagation of uncertainty depends on the type of arithmetic operation performed on...