Electromagnetic Propagation, Localization and Lasing in Random and Periodic Media

Abstract

Our measurements of the frequency and spatial variation of the microwave field in ensembles of random samples have revealed the underlying structure of wave correlation and photon localization. The intensity correlation was found in terms of displacement and polarization shift of the source and detector can be expressed in terms of the square of the corresponding field correlation function. Nonexponential decay of pulsed transmission through disordered media was found in nominally diffusive media, in which the level width exceeds the spacing between levels. This departure from diffusion theory is interpreted in terms of the decay rate statistics of electromagnetic quasi-normal modes. The influence of these modes of the electromagnetic field is an indication of the breakdown of the particle diffusion theory. Measurements of spatial and polarization correlation as a function of time delay from an exciting pulse show that the structure of the intensity correlation function is the same as found in steady state propagation, being a function only of the corresponding field correlation functions. The degree of correlation in the speckle pattern is seen to be the key parameter in dynamics and hence in steady state propagation. We have discovered a localization laser in random one dimensional systems.

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Document Details

Document Type
Technical Report
Publication Date
Dec 30, 2003
Accession Number
ADA422634

Entities

People

  • A. Z. Genack

Organizations

  • City University of New York

Tags

Communities of Interest

  • Advanced Electronics

DTIC Thesaurus Topics

  • Band Gaps
  • Detectors
  • Diffusion
  • Diffusion Theory
  • Dynamics
  • Electromagnetic Fields
  • Frequency
  • Frequency Shift
  • Intensity
  • Lasers
  • Liquid Crystals
  • Polarization
  • Probability Distributions
  • Radiation
  • Scattering
  • Statistics
  • Wave Propagation

Fields of Study

  • Physics

Readers

  • Atmospheric Science / Meteorology, specifically Wind Wave Turbulence.
  • Optical Physics and Photonics.
  • Quantum spin resonance or Electron Paramagnetic Resonance spectroscopy.

Technology Areas

  • Directed Energy
  • Space