GENERAL SCIENTIFIC SUMMARY
Introduction and background. The coherence and polarization of light beams are two aspects of statistical optics which can be treated in a unified manner. In 2003 Wolf proposed the unified theory of coherence and polarization of stochastic electromagnetic beams. Since then, a lot of work has been done on the propagation of stochastic electromagnetic beams in free space, through a turbulent atmosphere, through a gradient-index fiber, and through various complex optical systems. However, all the above investigations have been restricted to stationary beams.

Main results. The unified theory of coherence and polarization proposed by Wolf is extended from stochastic stationary electromagnetic beams to stochastic spatially and spectrally partially coherent electromagnetic pulsed beams. The analytical expression for the cross-spectral density matrix is derived, and used to formulate the spectral density, spectral degree of polarization and spectral degree of coherence of stochastic electromagnetic Gaussian Schell-model pulsed beams propagating in free space. The stationary electromagnetic beams, spectrally fully coherent electromagnetic pulsed beams and spatially fully coherent electromagnetic pulsed beams can be regarded as special cases of stochastic spatially and spectrally partially coherent electromagnetic pulsed beams. Some numerical examples are given to illustrate the application of the theory.

Wider implications. The results obtained in this paper will be useful for further study of more general types of stochastic electromagnetic pulsed beams in a unique way, and for exploring their potential applications.

41.20.Jb Electromagnetic wave propagation; radiowave propagation

02.50.Ey Stochastic processes

Computational physics

Accelerators, beams and electromagnetism

Issue 8 (August 2009)

Received 12 May 2009

Published 4 August 2009