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Electromagnetic energy stored in inhomogeneous scattering systems
Summary
This study derives a new formula for energy transport velocity in disordered media, independent of scatterer shape. Enhanced electromagnetic energy is found for specific inclusion properties, leading to high-quality factors in backscattering media.
Area of Science:
- Electromagnetism
- Condensed Matter Physics
- Wave Phenomena
Background:
- Disordered media exhibit complex wave propagation phenomena.
- Understanding energy storage and transport is crucial for material properties.
Purpose of the Study:
- To analytically derive the energy-transport velocity in disordered media with arbitrary inclusions.
- To establish a relationship between dwell time and absorption time.
- To approximate electromagnetic energy storage within disordered media.
Main Methods:
- Analytical derivation assuming low inclusion density.
- Analysis of internal energy and absorption cross-section.
- Development of an approximation based on transport mean free path and packing fraction.
Main Results:
- A novel expression for energy-transport velocity, independent of scatterer shape.
- A relationship connecting dwell and absorption times.
- An approximation for stored electromagnetic energy, dependent on scattering asymmetry parameters.
Conclusions:
- Enhanced electromagnetic energy is achievable with specific inclusion properties (negative scattering asymmetry).
- Disordered media with enhanced backscattering are predicted to have large quality factors.
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