Accession Number:

ADA422634

Title:

Electromagnetic Propagation, Localization and Lasing in Random and Periodic Media

Descriptive Note:

Final rept. 9 Jun 2000-30 Oct 2003

Corporate Author:

CITY UNIV OF NEW YORK RESEARCH FOUNDATION

Personal Author(s):

Report Date:

2003-12-30

Pagination or Media Count:

13.0

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.

Subject Categories:

  • Electricity and Magnetism
  • Radiofrequency Wave Propagation

Distribution Statement:

APPROVED FOR PUBLIC RELEASE