Depolarization of a Laser Beam in a Turbulent Medium

Abstract

The correlation function of the depolarized component of a finite collimated gaussian laser beam in a turbulent medium is determined. The correlation function is then specifically evaluated for a turbulent medium which is characterized by (a) a gaussian spectrum or (b) a Kolmogorov spectrum. In both cases, the contribution of the finite laser beam can lead to an increase in the magnitude of the correlation function which is comparable and possibly greater than the plane-wave case. For either the gaussian or Kolmogorov spectrum, however, the magnitude of the depolarization is still very small. Finally, by allowing the beam radius to go to infinity, we obtain the plane-wave result and for the gaussian and Kolmogorov spectra the result is found to be identical to the plane-wave case derived by Strohbehn and Clifford, and Strohbehn, respectively.